Kosovo's president, Hashim Thaci, along with nine other former separatist fighters, have been indicted for alleged war crimes and crimes against humanity during Kosovo's 1998-99 uprising against Serbian rule.

The ruling, announced on Wednesday, comes from the Specialist Prosecutor's Office (SPO) in The Hague, set up in 2015 to deal with cases of alleged crimes by Kosovo Liberation Army (KLA) guerrillas in the late 1990s.

According to the court, the indictment is "the result of a lengthy investigation and reflects the SPO's determination that it can prove all of the charges beyond a reasonable doubt." 

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The office is accusing Thaci and the nine others of being "criminally responsible for nearly 100 murders," but the specifics of the war crimes are yet to be released. 

The former speaker of Kosovo's parliament, Kadri Veseli, is one of the names to appear on the list of the indictments. Thaci and Veseli, both former commanders in the KLA, have previously denied being involved in any war crimes during the conflict. 

The SPO also stated the men were thought to have "carried out a secret campaign to overturn the law that created the Court and otherwise obstruct the work of the Court in an attempt to ensure that they do not face justice."

The KLA was first accused of war crimes in a 2011 report by the Council of Europe rights agency, in which fighters were alleged to have killed ethnic Albanian political opponents and civilian Serbs between 1998 and 1999. And Kosovo's independence is not globally recognized. 

The SPO, which is governed by Kosovan law but staffed by international prosecutors, is based in the Netherlands partly to help ensure protection of witnesses. 

Following the release of the indictments, Thaci's office said a delegation of Kosovo's top brass, including Prime Minister Avdullah Hoti had cancelled a trip to Washington for what was to be the first round of U.S.-mediated talks with Serbia on normalizing relations.

More than 10,000 people were killed during the conflict in the 1990s — most of them ethnic Albanians — with the fighting coming to a halt following a 78-day NATO air campaign against Serbian forces. 

Despite 30 agreements having been made during EU-facilitated negotiations between Kosovo and Serbia since 2011, tensions remain high, with Kosovan officials stating that the indictment was politically motivated.