The EU justice mission on Friday charged 15 former Kosovo rebel fighters for alleged war crimes including murder and torture committed during the 1998-1999 war with Serbian forces.
The identities of the defendants were not revealed, but local media reported that they include former KLA commander Sylejman Selimi, who is now Kosovo's ambassador to Albania, and Sami Lushtaku, mayor of northern town Srbica and a top official in Prime Minister Hashim Thaci's ruling party.
"The defendants are charged with... war crimes against civilian population, including torture, mistreatment of prisoners, and murder" allegedly carried out in a detention centre run by guerrilla Kosovo Liberation Army (KLA) in 1998, said a statement by the mission called EULEX.
The detention centre was located in the northwestern Drenica region, the wartime stronghold of the ethnic Albanian guerrillas fighting the armed forces of then Serbian strongman Slobodan Milosevic.
War veterans' associations condemned the indictment, calling it "politically motivated".
Some 13,000 people were killed in the war which ended when a NATO-led air campaign halted Milosevic's crackdown on the pro-independence Kosovo Albanians and ousted his forces from the territory in June 1999.
The 3,000-member EULEX mission was launched in December 2008 to enforce the rule of law in Kosovo.
It has the power to step in and take on cases that the local judiciary and police are unable to handle because of their sensitive nature.
Friday's indictment is the third high-profile war crimes case launched by EULEX.
In June, three former KLA commanders were convicted for abusing civilian detainees in a guerrilla-run prison.
And in September, Fatmir Limaj -- a former top KLA commander who is now deputy of Thaci's Democratic party of Kosovo, and nine other people who were indicted for abusing Serb and Albanian civilians at a detention centre, were acquitted.