A UN court in The Hague has cleared a former Kosovo Albanian rebel commander of war crimes charges relating to the conflict with Serb forces in 1998.
Fatmir Limaj was brought to The Hague in early 2003
The acquittal of Fatmir Limaj, 34, was greeted with street celebrations in the Kosovo capital, Pristina.
Mr Limaj's co-accused, Isak Musliu, was also cleared of all charges.
A third man, Haradin Bala, was found guilty of war crimes. He becomes the first Kosovo Albanian to be convicted by the UN's war crimes court.
Bala will serve a 13-year jail term for the mistreatment and murder of Serb civilian prisoners and their alleged Albanian collaborators.
The UN court was set up to try war crimes and crimes against humanity from the conflicts that accompanied the disintegration of the former Yugoslavia in the 1990s.
Several Serbs, Croats and Bosnian Muslims have already been jailed by the court.
The tribunal has been criticised for bias against Serbs and for not bringing more ethnic Albanians to trial, reports the BBC's Hague correspondent, Geraldine Coghlan.
Prosecutors at the court say it is hard for them to build indictments against Kosovo Albanians because witnesses are afraid of coming forward.
Kosovo Albanian politicians praised the decision to acquit Mr Limaj, a former commander in the Kosovo Liberation Army (KLA).
"The verdict proves that our war against the Serb occupation and for independence for our country, and our hopes placed in international justice, were justified," Kosovo President Ibrahim Rugova said.
The province's Prime Minister, Bajram Kosumi, said the verdict "proves that Limaj and his compatriots had just one goal in their lives - the freedom of Kosovo".
In Pristina, crowds celebrated the verdict with gunfire and the tooting of car horns, reports say.
However, politicians in the Serbian capital, Belgrade, have attacked the verdict.
Presidential adviser Jovan Simic told Serb TV the court decision sends out "a very bad message".
Mr Limaj, Mr Musliu and Haradin Bala were the first Kosovo Albanians to be indicted.
KLA fighters battled Serb forces until Nato's intervention in 1999
Prosecutors had accused the three men of detaining 35 people - including Serbs and alleged Albanian collaborators - in the camp, where they were subjected to torture and inhumane conditions.
The three were also accused of executing several prisoners as they fled a Serb assault on the Lapusnik region.
The presiding judge, Kevin Parker, said the prosecution had successfully proven the existence of a prison camp at Lapusnik, near Pristina.
The judge said Bala's presence at the camp had been proven beyond any doubt, but there was not enough evidence to link Mr Limaj and Mr Musliu to the crimes committed there.
Final status talks
Three more Kosovo Albanians have since been indicted, including the former Prime Minister and guerrilla commander, Ramush Haradinaj, who is currently awaiting trial.
The KLA conducted a guerrilla war against Serb forces, whom they accused of launching a crackdown on the province's ethnic Albanian community.
A 78-day Nato air campaign in 1999 drove Serbian forces out of the province.
Kosovo has since been administered by the United Nations and Nato, though it technically remains a province of Serbia.
The area's Albanian majority wants full independence - but Belgrade has said it must remain part of Serbia.
The UN envoy to the province has said talks to resolve its final status must begin soon.