PRISTINA (Reuters) - Kosovo’s Supreme Court ordered a retrial of doctors and officials convicted of involvement in an organ trafficking ring that performed dozens of illegal kidney transplants between 2006 and 2008, in a ruling published on Friday.

The European police and justice mission in Kosovo (EULEX), established to help the Balkan country develop its justice system, said it was disappointed with the ruling.

The ring acted out of the Medicus clinic on a residential road on the outskirts of the capital Pristina.

Kidney donors from Turkey and poor parts of the former Soviet Union were promised 10,000-12,000 euros, while recipients, mainly Israelis, paid 80,000-100,000 euros for the organs, an earlier hearing heard.

The Medicus verdict is the highest-profile case handled by EU prosecutors and judges who arrived in Kosovo in 2008 to handle sensitive cases such as war crimes, organized crime and corruption.

EULEX is now planning to leave Kosovo and independent law monitors fear local justice may reopen some sensitive cases.

The director of the clinic, urologist Lutfi Dervishi, was jailed for eight years for organized crime and human trafficking and his son for seven years in 2013.

Both men went into hiding and never served the sentence.

Four other people, including Health Ministry officials, received lesser terms but never served time following appeal after appeal in different courts.

The Supreme Court’s panel of judges comprising two local and one international judge annulled the court ruling citing procedural irregularities and ordered a retrial after the defendants appealed the case.

“The mission expresses its disappointment with the outcome of the Medicus case, where a local-majority panel annulled all previous judgments in the parts where the defendants have been convicted,” EULEX spokeswoman Besa Domi told Reuters.