The Ten-Day War (Slovene: desetdnevna vojna), or the Slovenian War of Independence (slovenska osamosvojitvena vojna), was a brief conflict that followed Slovenia's declaration of independence from Yugoslavia on 25 June 1991. It was fought between the Slovenian Territorial Defence (Slovene: Teritorialna obramba Republike Slovenije) and the Yugoslav People's Army (JNA). It lasted from 27 June 1991 until 7 July 1991, when the Brioni Accords were signed. It marked the beginning of the Yugoslav Wars.
Following the death of Yugoslav president Josip Broz Tito in 1980, underlying political, ethnic, religious, and economic tensions within Yugoslavia surfaced. In 1989 Slobodan Milo?evi?, Chairman of the Central Committee of the League of Communists of Serbia since 1986, became president of Serbia, the largest and most populous of the six Yugoslav republics. As Milo?evi? moved to consolidate power by centralizing the state, the governments of the other republics sought to loosen the central grip on power by devolving as much constitutional power as possible to each of the republics and autonomous provinces. A series of disagreements among delegates persisted until four of the six republics each made the decision to gain independence from Yugoslavia. Supported by Germany and the Vatican, Slovenia was among those republics aiming for independence.
The first action in defence of Slovenian independence, that united both the opposition and democratized communist establishment in Slovenia was, however, carried out by the Slovene police forces, in an action named Action North in 1989. In April 1990, Slovenia held its first democratic multi-party elections, won by the DEMOS coalition.
On 23 December 1990, Slovenia held a referendum, which passed with 88.5% of overall electorate supporting independence (94.8% of votes cast), with a turnout of 93.3%. The Slovenian government was well aware that the federal government in Belgrade might seek to use military force to quash Slovenia's move towards independence. Immediately after the Slovenian elections, the Yugoslav People's Army (JNA / Slovene: Jugoslovanska ljudska armada [JLA]) announced a new defence doctrine that would apply across the country. The Tito-era doctrine of "General People's Defence", in which each republic maintained a Territorial Defence Force (Teritorialna obramba, or TO), was to be replaced by a centrally directed system of defence. The republics would lose their role in defence matters, and their TOs would be disarmed and subordinated to the YPA's headquarters in Belgrade.
The Slovenian government resisted these moves and successfully ensured that the majority of Slovenian Territorial Defence (TO) equipment was kept out of the hands of the YPA. It also declared in a constitutional amendment passed on 28 September 1990 that its TO would be under the sole command of the Slovenian government. At the same time, the Slovenian government set up a secret alternative command structure, known as the Manoeuvre Structures of National Protection (Manevrska struktura narodne zaite, or MSNZ). This was an existing but antiquated institution, unique to Slovenia, which was intended to enable the republic to form an ad hoc defence structure, akin to a Home Guard. It was of negligible importance prior to 1990, with antiquated weapons and few members. However, the DEMOS-led government realised that the MSNZ could be adapted to provide a parallel organisation to the TO that would be entirely in the hands of the Slovenian government.
When the YPA tried to take control of the Slovenian Territorial Defence, the TO's command structure was simply replaced by that of the parallel MSNZ. Between May and October 1990, some 21,000 Slovenian Territorial Defence and police personnel were secretly mobilised into the MSNZ command structure, of which the federal government was wholly unaware. The Slovenian government also undertook detailed planning of a military campaign against the YPA, which resulted in the production of an operational and tactical plan by November 1990 - over seven months before the conflict actually began.
The Slovenes were aware that they would not be able to deter the YPA's forces for an extended period of time. Under Defence Minister Janez Jan?a, they adopted a strategy based on an asymmetric warfare approach. TO units would carry out a guerrilla campaign, using anti-tank weapons and anti-aircraft missiles to ambush the YPA's units. Tank columns could be trapped by destroying the lead and rear vehicles in favourable terrain - for instance, on a narrow mountain road where room for manoeuvre was limited – enabling the rest to be tackled more easily. In preparation for this, the Slovenian government covertly bought lightweight missile systems from foreign suppliers, notably the SA-7 Grail (Strela) anti-aircraft missile and the German-designed Armbrust anti-tank system. Hit-and-run and delaying tactics were to be preferred and frontal clashes were to be avoided since in such situations the YPA's superior firepower would have been very difficult to overcome.
Slovenia and Croatia passed the acts about their independence on 25 June 1991. This "advance" on the date of independence was a critical element of the Slovenian plan to gain an early advantage in the expected conflict. The Slovenian government fully expected the Yugoslav military to respond with force on the day of the declaration of independence or shortly afterwards. By secretly advancing the date by 24 hours, the Slovenians wrongfooted the Yugoslav government, which had set 26 June as the date for its move.
Although the Yugoslav army was adamantly opposed to Slovenian independence, it was divided about what to do. The YPA Chief of Staff, Colonel-General Blagoje Ad?i?, advocated a large-scale military operation to remove the Slovenian government and bring "healthy forces" to power in the republic. His political superior, the Yugoslav Defence Minister General of the Army Veljko Kadijevi?, insisted on a more cautious approach – essentially a show of force that would convince the Slovenian government to back down on its declaration of independence. After some debate, Kadijevi? got his way.
It is unclear how much the civilian members of the Yugoslav government were involved in the decision to resort to force in Slovenia. Ante Markovi?, the President of the Federal Executive Council (equivalent to Prime Minister) is reported to have said that the federal government had not been informed of the Army's actions.
On the morning of 26 June, units of the Yugoslav People's Army's 13th Corps left their barracks in Rijeka, Croatia, to move towards Slovenia's borders with Italy. The move immediately led to a strong reaction from local Slovenians, who organized spontaneous barricades and demonstrations against the YPA's actions. There had been no fighting yet, and both sides appeared to have an unofficial policy of not being the first to open fire.
By this time, the Slovenian government had already put into action its plan to seize control of the republic's border posts and the international airport at Brnik. The personnel manning the border posts were, in most cases, already Slovenians, so the Slovenian take-over mostly simply amounted to changing of uniforms and insignia, without any fighting. This was undertaken, in the words of Janez Jan?a, to "establish our sovereignty in the key triangle, border-customs-air control." It also had important practical effects. The border crossings were a major source of revenue. In addition, by taking control of the borders, the Slovenians were able to establish defensive positions against an expected YPA attack. This meant that the YPA would have to fire the first shot. It was fired on 27 June at 14:30 in Diva?a by an officer of the YPA.
Further YPA troop movements took place in the early hours of 27 June. A unit of the YPA's 306th Anti-Aircraft Regiment, based in Karlovac, Croatia, crossed the Slovenian border at Metlika. A few hours later, a column of tanks and armoured personnel carriers of the YPA 1st Armoured Brigade left their barracks at Vrhnika near the Slovenian capital Ljubljana, heading for the airport at Brnik. They arrived a few hours later and took control of the facilities. As the YPA was the federal army, its forces were customarily deployed in various places within the federal republics including Slovenia. To the east, YPA units left Maribor heading for the nearby border crossing at ?entilj and the border town of Dravograd further west. The Yugoslav Air Force aircraft dropped leaflets over various parts of Slovenia bearing the messages "We invite you to peace and cooperation!" and "All resistance will be crushed."
In the early hours of 27 June the Slovenian leadership was told of the movements of the YPA. The military leadership of the Fifth Military District, which included Slovenia, was in telephone contact with Slovenian president Milan Ku?an, telling him that the troops' mission was limited to taking over the border crossings and airport. A meeting of the Slovene presidency was hastily convened at which Ku?an and the rest of the members decided on armed resistance.
The Slovenian government had received warnings that the YPA would use helicopters to ferry special forces troops to strategic locations. It issued a warning to the YPA's 5th Military Command District in Zagreb that if helicopters continued to be used they would be shot down. The warning was disregarded by the YPA leadership, which still believed that the Slovenians would back down rather than fight. This was, however, a disastrous miscalculation. In the afternoon of 27 June, the Slovenian TO (Slovenian Territorial Defence) shot down two YPA helicopters with SA-7 missiles, one of them a Gazelle over Ro?na Dolina, Ljubljana, killing the occupants (one of whom, Toni Mrlak, was a Slovenian pilot, as the YPA's forces consisted of nationals from all the republics). The Slovenian Territorial Defence also took up positions around YPA barracks in various locations, effectively besieging them, and launched a series of attacks on YPA forces across Slovenia. At Brnik, a Slovenian TO unit attacked the YPA troops holding the airport, and at Trzin a firefight developed in which four YPA soldiers and one Slovenian TO soldier (Edvard Peperko) were killed and the remainder of the YPA unit was forced to surrender. Attacks were also launched by Slovenian TO units on YPA tank columns at Pesnica, Ormo? and Koseze near Ilirska Bistrica. A tank column from the YPA's 32nd Mechanised Brigade, advancing from Vara?din in Croatia, was blocked at Ormo? near the Slovenian border and found itself unable to break through a Slovenian barricade.
Despite the confusion and fighting, the YPA nonetheless successfully accomplished much of its military mission. By midnight on 27 June it had captured all of the crossings along the Italian border, all but three crossings on the Austrian border and several of the new crossing points established along Slovenia's border with Croatia. However, many of its units were still stuck in vulnerable positions across Slovenia.
During the night of 27-28 June, Slovenian TO units were ordered to undertake a general offensive against the YPA. The Slovenian defence ministry ordered:
At all locations where RS (Republic of Slovenia) armed forces (Slovenian Territorial Defence) have the tactical advantage, offensive actions against enemy units and facilities will be carried out. The enemy will be summoned to surrender, the shortest deadline possible for surrender given and action taken using all available weapons. While in action, any necessary arrangements will be made to evacuate and protect the civilians.
Additional fighting took place throughout the day. The YPA tank column that had been attacked at Pesnica the previous day was blocked by impromptu barricades of Slovenian trucks at ?trihovec, a few kilometers short of the border with Austria, where it again came under attack by Slovenian TO personnel and Slovenian police. The SFR Yugoslav Air Force mounted two airstrikes in support of the YPA forces at Strihovec, killing four truck drivers. At Medvedjek in central Slovenia, another YPA tank column came under attack at a truck barricade, where air raids killed six truck drivers. Heavy fighting broke out at Nova Gorica on the border with Italy, where the Slovenian Special Forces fired two Armbrust antitank rockets and fired 700 rounds from infantry weapons. Slovene troops destroyed two YPA T-55 tanks and captured an additional three, plus a BTS-1 military engineering vehicle. Three YPA soldiers were killed and 16 wounded, among them the commander of the armored column, and 98 surrendered. A number of wounded were admitted to Gorizia's hospital after crossing the Italian border. Some sources claim that this was the decisive battle of the war.
The border crossing at Holmec was captured by Slovenian TO forces. Two Slovenian and three YPA soldiers were killed, and 91 YPA soldiers captured. The YPA barracks at Bukovje Mansion in Bukovje near Dravograd were attacked by Slovenian TO units and a YPA weapons depot at Borovnica fell to the Slovenian TO, significantly improving the Slovenians' supply of weapons. The Yugoslav Air Force carried out attacks at a number of locations across the country, most notably at Brnik Airport, where two journalists from Austria and Germany (Nikolas Vogel and Norbert Werner) were killed and four Adria Airways airliners were seriously damaged. The Yugoslav Air Force also attacked the Slovenian TO military headquarters at Ko?evska Reka and flew sorties against radio and television transmitters at Krim, Kum, Trdina Peak, and Nanos in an attempt to silence the Slovenian government broadcasts.
By the end of the day, the YPA still held many of its positions but was rapidly losing ground. YPA was beginning to experience problems with desertions - many Slovenian members of the YPA quit their units or simply changed sides - and both the troops on the ground and the leadership in Belgrade appeared to have little idea of what to do next.
The outbreak of the war galvanised diplomatic efforts by the European Community to find an end to the crisis. Three EC foreign ministers met with Slovenian and Yugoslav government representatives in Zagreb during the night of 28-29 June and agreed on a ceasefire plan, but this was not put into practice. In the morning, the Slovenians achieved several significant military successes. The YPA troops at Ljubljana Airport near Brnik surrendered to Slovenian TO forces, who had surrounded the facility overnight. In the north, several YPA tanks were captured near Strihovec and later reorganised into a TO tank company. YPA special forces attempted a maritime landing at Hrvatini but were ambushed and repulsed by the Slovenians. The YPA-held border crossings at Vrtojba and ?entilj also fell to the Slovenian TO, who seized the federal troops' weapons and tanks, providing a much-needed boost to their arsenal.
The YPA issued an ultimatum to Slovenia, demanding an immediate cessation of hostilities by 09:00 on 30 June. In response, the Slovenian Assembly adopted a resolution calling for a peaceful solution to the crisis that did not jeopardise Slovenian independence, and rejected the YPA ultimatum.
Skirmishing continued in several places during the day. Slovenian forces seized the strategic Karawanken Tunnel under the Alps on the border with Austria and captured nine YPA tanks near Nova Gorica. The entire YPA garrison at Dravograd - 16 officers and 400 men, plus equipment - surrendered, and the garrisons at Tolmin and Bovec also fell to the Slovenians. The weapons captured from the garrisons were quickly re-issued to the Slovenian forces.
More skirmishes took place, with Slovenian TO forces taking over a YPA facility at Nova vas, south of Ljubljana. The YPA's ammunition dump at ?rni Vrh caught fire and was destroyed in a massive explosion, damaging much of the town. However, the Slovenians successfully captured depots at Pe?ovnik, Bukov?lak, and Zalo?ka Gorica, taking possession of some 70 truckloads of ammunition and explosives.
The YPA 306th Light Air Defence Artillery Regiment's column retreated from its exposed position at Medvedjek and headed into the Krakovo Forest (Krakovski gozd) near the Croatian border. It ran into a blockade near the town of Kr?ko and was surrounded by Slovenian forces, but refused to surrender, probably hoping for help from a relief column.
In the meantime, the YPA's leadership sought permission to change the tempo of its operations. Defence Minister Veljko Kadijevi? informed the Yugoslav cabinet that the YPA's first plan - a limited operation to secure Slovenia's border crossings - had failed, and that it was time to put into operation the backup plan of a full-scale invasion and imposition of military rule in Slovenia. However, the collective presidency - headed at the time by Serbia's Borisav Jovi? - refused to authorise such an operation. The YPA Chief of Staff, General Blagoje Ad?i?, was furious and publicly denounced "the federal organs [which] continually hampered us, demanding negotiations while they [the Slovenians] were attacking us with all means."
The heaviest fighting of the war to date took place during 2 July. The Dom?ale radio transmitter was attacked at 10:37 UTC (11:37 local time) and heavily damaged by two YPA MiG-21 planes. During the rest of the day there were a number of major set-backs for the YPA. The YPA convoy in the Krakovo Forest came under sustained attack from TO units, forcing it to surrender. Units from the YPA's Fourth Armoured Brigade attempted to move up from Jastrebarsko in Croatia but were beaten back near the border town of Bregana. The Slovenian TO mounted successful attacks on border crossings at ?entilj, Gornja Radgona, Ferneti?i and Gorjansko, overrunning them and taking a number of YPA troops prisoner. A protracted engagement between YPA and Slovenian TO forces took place during the afternoon and evening at Dravograd, and a number of YPA facilities around the country fell to Slovenian forces.
At 21:00, the Slovenian Presidency announced a unilateral ceasefire. However, this was rejected by the YPA leadership, which vowed to "take control" and crush Slovenian resistance.
A large YPA armoured convoy set off from Belgrade on the morning of 3 July, ostensibly to go to Slovenia. It never arrived; according to the official account, this was due to mechanical breakdowns.
Fighting continued in Slovenia, with a YPA relief force heading for the Gornja Radgona border crossing being halted near Radenci. YPA forces at the Kog border crossing were also attacked by TO units. In the evening, the YPA agreed to a ceasefire and a withdrawal to barracks. In a separate incident not far from Radenci, in the village of Hrastje-Mota, a Yugoslav Mi-8 helicopter developed mechanical problems and was forced to land. The helicopter was seized by the Slovene military, but was deemed not suitable for the newly born air force and handed back to Belgrade on 13 August.
With a ceasefire now in force, the two sides disengaged. Slovenian forces took control of all of the country's border crossings, and YPA units were allowed to withdraw peacefully to barracks and to cross the border to Croatia.
The Ten-Day War was formally ended with the Brioni Accord, signed on the Croatian Brijuni Islands. Slovenian and Croatian independence were agreed to. The terms were distinctly favourable to Slovenia; it was agreed that Slovenia and Croatia would postpone their independence for three months--which in practical terms had little real impact--and the Slovenian police and armed forces (Slovenian Territorial Defence) were recognised as sovereign on their territory.
It was agreed that all Yugoslav military units would leave Slovenia, with the Yugoslav government setting a deadline of the end of October to complete the process. The Slovenian government insisted that the withdrawal should proceed on its terms; the YPA was not allowed to take much of its heavy weaponry and equipment, which was later either deployed locally or sold to other Yugoslav republics. The withdrawal began about ten days later and was completed by 26 October.
Due to the short duration and low intensity of the war, casualties were not high. According to Slovenian estimates, the YPA suffered 44 fatalities and 146 wounded, while the Slovenians had 19 killed and 182 wounded. Twelve foreign nationals were killed in the conflict, principally journalists and Bulgarian truck drivers who had strayed into the line of fire. 4,692 YPA soldiers and 252 federal police officers were captured by the Slovenian side. According to post-war assessments made by the YPA, its material losses amounted to 31 tanks, 22 armoured personnel carriers, 6 helicopters, 6,787 infantry weapons, 87 artillery pieces and 124 air defence weapons damaged, destroyed or confiscated. Property damage was not heavy, due to the scattered and short-term nature of the fighting.
The border station at Holmec was the location of an alleged war crime perpetrated by Slovenian TO forces, filmed by the Austrian public broadcasting station ORF. Video footage shows a small group of YPA soldiers standing or walking slowly with raised hands, holding up a white sheet in an apparent attempt to surrender. Moments later, gunfire is heard and the soldiers fall or jump to the ground. Neither the origin of the gunfire nor its exact effect are clearly visible on the video segment. Slovene officials maintain that the YPA soldiers jumped for cover and were not hit, and that the matter was thoroughly investigated years ago. However, the incident sparked renewed public debate after the footage was shown on Serbian TV station B92 in 2006, with many claiming that the soldiers were shot and killed by Slovenian TO troops and that Slovenia is trying to cover up the affair.
The fate of the YPA soldiers identified on the footage is disputed. One report claims that the soldiers are still alive, 15 years after the conflict. Other reports identify three young soldiers as victims (Zoran Je?i?, Goran Maleti? and Antonio ?imunovi?) and claim that they were killed in the Holmec incident.
The actions of Slovenia's forces were largely dictated by the military strategy devised some months before and were tightly integrated with an equally detailed media management plan. An international media centre was established prior to the outbreak of conflict with Jelko Kacin designated to act as information minister and Slovenia's public face to the world. The Slovenian government and media successfully presented the conflict to Western European audiences as a case of a "David versus Goliath" struggle between an emerging democracy and an authoritarian communist state, and the columns of Yugoslav tanks brought to mind the events of the Tiananmen Square protests of 1989 two years earlier. This won considerable international sympathy and favourable media coverage for the cause of independent Slovenia.
The Slovenians had the advantage of superior morale, compared to their adversaries in the Yugoslav army. Many of the Yugoslav soldiers did not realise they were taking part in a real military operation, rather than an exercise, until they came under attack. The officer corps was dominated by Serbs and Montenegrins and in many cases ideologically committed to Yugoslav unity. The rank and file troops however were conscripts, many of whom had no strong motivation in fighting against Slovenes. Of the soldiers of the 5th Military District, which was in action in Slovenia, in 1990 30% were Albanians, 20% Croats, 15 to 20% Serbs and Montenegrins, 10% Bosniaks, and 8% Slovenes.
The Slovenians were also well aware that the Serbian government of Slobodan Milo?evi? was not particularly concerned about Slovenia's independence, given the lack of any significant Serbian minority in the country. On 30 June, Defence Minister General Kadijevi? suggested to the Yugoslav federal presidency a massive attack on Slovenia to break down the unexpectedly heavy resistance. But the Serb representative, Borisav Jovi?, shocked the military establishment by declaring that Serbia did not support further military action against Slovenia. Serbia was at this point more concerned with the situation in Croatia; even before the war had ended, YPA troops were already repositioning themselves for the imminent war in Croatia.
For Slovenia, the war marked the decisive defence of its independence in regard to Yugoslavia. It was officially recognised by all European Community member states on 15 January 1992 and joined the United Nations on 22 May.
The war led to a series of major shifts on the Yugoslav side. The YPA eventually lost nearly all of its Slovenian and Croat personnel, becoming an almost entirely Serbian and Montenegrin force. Its poor performance in Slovenia and later in Croatia discredited its leadership - Kadijevi? resigned as defence minister in January 1992, and Ad?i? was forced into medical retirement shortly afterwards.
The Slovenian and Croatian governments were urged by the European Commission to freeze their declaration of independence for a period of three months, hoping to ease tension, to which Slovenia and Croatia agreed. Slovenia used the period to consolidate its institutions, deliver some of the most urgent economic reforms and prepare for international recognition of the country.