Kosovo's prime minister, Hashim Thaçi, has been identified as one of the "biggest fish" in organised crime in his country, according to western military intelligence reports leaked to the Guardian.

The Nato documents, which are marked "Secret", indicate that the US and other western powers backing Kosovo's government have had extensive knowledge of its criminal connections for several years.

They also identify another senior ruling politician in Kosovo as having links to the Albanian mafia, stating that he exerts considerable control over Thaçi, a former guerrilla leader.

Marked "USA KFOR", they provide detailed information about organised criminal networks in Kosovo based on reports by western intelligence agencies and informants. The geographical spread of Kosovo's criminal gangs is set out, alongside details of alleged familial and business links.

[On 25 January] the Council of Europe is expected to formally demand an investigation into claims that Thaçi was the head of a "mafia-like" network responsible for smuggling weapons, drugs and human organs during and after the 1998-99 Kosovo war.

The organ trafficking allegations were contained in an official inquiry published last month by the human rights rapporteur Dick Marty.

His report accused Thaçi and several other senior figures who operated in the Kosovo Liberation Army (KLA) of links to organised crime, prompting a major diplomatic crisis when it was leaked to the Guardian last month.

The report also named Thaçi as having exerted "violent control" over the heroin trade, and appeared to confirm concerns that after the conflict with Serbia ended, his inner circle oversaw a gang that murdered Serb captives to sell their kidneys on the black market.

The Council's of Europe's parliamentary assembly in Strasbourg will debate Marty's findings and vote on a resolution calling for criminal investigations. The vote is widely expected to be passed. Read full article in Guardian...