At the end of a two-year trial in Milan, Judge Oscar Magi sentenced two Italian spies and 23 U.S. citizens, all but one CIA agents, in absentia to prison sentences of up to eight years for the kidnapping of Hassan Mustafa Osama Nasr, known as Abu Omar. The radical Muslim cleric was snatched by a group of U.S. and Italian agents off a busy Milan street in broad daylight.
The verdict is the first against a dubious anti-terror practice known as "extraordinary rendition," in which a suspect is kidnapped and taken to a third country for interrogation.
It puts pressure on Washington to steer a clear course on the practice, which has been criticized by most European nations.
"The Milan court sent a powerful message: The CIA can't just abduct people off the streets," Joanne Mariner, terrorism program director at Human Rights Watch, told the Chicago Tribune. "It's illegal, unacceptable and unjustified."
Virtually all rendition victims claim they have been abused, some even say tortured.
Abu Omar, who was suspected of having recruited men for the insurgency in Iraq and Afghanistan, was flown via air bases in Italy and Germany to Egypt, where he says he was abused for months.
The Obama administration has so far not decided whether it wants to prosecute CIA agents who have committed crimes related to extraordinary renditions.
CIA officials have said renditions might continue, albeit under closer oversight, ensuring that no crimes are committed and that suspects are treaty humanely. (Washington doesn't see rendition as a crime, and a major U.S. court has yet to render a verdict on the issue).
Armando Spataro, the lead prosecutor of the Milan trial, said the ruling is a warning to governments around the world.
"The message of this important ruling -- to nations, governments, institutions, secret services, etc. -- is that we cannot use illegal instruments in our effort against terrorism. Our democracies, otherwise, would betray their principles," he was quoted as saying by the Chicago Tribune.
The CIA has not yet commented on the trial, nor has it ever admitted that its agents were involved in the kidnapping of Abu Omar.
Earlier this year Robert Seldon Lady, a senior CIA officer in Milan who was sentenced to eight years in prison, told Italy's Il Giornale newspaper that he was not guilty.
"I'm only responsible for carrying out orders that I received from my superiors," he told the paper.
The Americans are now warranted in Italy and may be extradited to the country by other EU nations if they travel to Europe.