A draft report by a European Parliament committee says European Union countries knew about secret prisons for terror suspects the CIA ran on their territories, despite statements to the contrary.
The report also says nearly all European Union member states and many senior EU officials were reluctant to cooperate with the investigation.
An interim report published in June named Poland and Romania as countries that may have allowed the CIA to operate the clandestine prisons on their territories.
It also says others may have violated individual rights by allowing the CIA to use their facilities for secret prisoner transfers.
International human rights groups have expressed concern over the possible torture of the detainees.
U.S. officials, including Secretary of State Condoleezza Rice and President Bush, have defended the program as legal under international law but stressed that the United States does not permit torture.
The final European Parliament report is expected early next year.
Some information for this report was provided by AFP, AP and Reuters.