Seven Kosovars went on trial in Pristina Tuesday, charged with trafficking in human organs.

All seven, including doctors and a former health ministry official, have pleaded not guilty.

The European Union rule of law mission in Kosovo is running the trial. Prosecutors allege that the defendants lured donors by promising to pay them as much as $20,000 for their kidneys and other organs, and reselling them for up to $133,000 to patients needing transplants.

Police uncovered the alleged scheme in 2008 when a Turkish man collapsed in pain at the Pristina airport after having his kidney removed.

European investigators also are looking into charges that ethnic Albanian rebels murdered Serbs and Albanians during the war in Kosovo in the late 1990s and sold their organs on the black market. Suspects include Kosovo Prime Minister Hashim Thaci, who denies the allegations.