An inquiry by the EU has found “compelling indications” that ten Serb captives had their body organs harvested for illegal trafficking during the 1998-99 Kosovo war. However, it wasn’t widespread and there will be no trial, the lead investigator said.

The chief prosecutor Clint Williamson, who led the investigation, said there was no evidence of widespread organ harvesting, but that the crime had occurred a number of times.

“There are compelling indications that this practice did occur on a very limited scale and that a small number of individuals were killed for the purpose of extracting and trafficking their organs,” he told journalists. However, he added that there would not be enough evidence at the moment to prosecute the alleged crimes.

The revelation was part of a presentation on a 2 1/2 year investigation into atrocities that also largely confirmed human right reports that there was a campaign of persecution against Serb, Roma and other minorities by some people in the Kosovo Liberation Army (KLA).

The investigation was prompted by a 2011 report by Council of Europe member Dick Marty that accused senior KLA commanders of involvement in the smuggling of Serb prisoners into northern Albania and the removal of their organs for sale.

Kosovo’s Prime Minister Hashim Thaci, himself a former KLA leader who was named in Marty’s report, has dismissed the accusations as an attempt to tarnish the Kosovo Albanian fight for independence.

“The government of the Republic of Kosovo appreciates the completion of the ambassador Williamson’s work, which is an important step to determine potential individual responsibility and gives an end to the claims of the unfounded charges,” Thachi said.

However, Williamson bitterly complained that the investigation had been made far more difficult because of “a climate of intimidation that seeks to undermine any investigations of individuals associated with the former Kosovo Liberation Army.”

Williamson did say the Special Investigative Task Force would in future be “in a position to file an indictment against certain senior officials of the former Kosovo Liberation Army” for a series of crimes, including killings, disappearances, camp detentions and sexual violence.

Without naming any individuals, Williamson said that “there are compelling indications that this practice did occur.” He went to lengths to make clear the alleged harvesting was not a wholesale practice, rejecting claims of hundreds of victims. Some 400 people, mostly Kosovo Serbs, disappeared near the end of the war, AP reports.

Just over 2,000 Serbs are believed to have been killed during and immediately after the war.

Serbia has vowed never to recognize the independence of its former province, which many Serbians consider their nation’s heartland, after it declared independence in 2008. It is also not recognized by dozens of countries worldwide, including Russia.

In Belgrade, Serbia’s war crimes prosecutor Vladimir Vukcevic told The Associated Press that Tuesday’s announcement “crowns a big effort on our part and shows that we were right when we said that war crimes had been committed and that organ trafficking took place.”