United States anti-terror policies are contravening human rights law, says Dick Marty, head of a European investigation into alleged CIA prisons in Europe.
At a media conference on Friday, the Swiss parliamentarian also criticised Switzerland and Europe for taking a passive attitude towards such policies.
Speaking in the town of Burgdorf in Switzerland, Marty, who is leading a probe on behalf of the Council of Europe, said that the US strategy did not respect international human rights and the Geneva Conventions.
He added that he was convinced that the CIA was undertaking illegal activities in Europe in its transportation and detention of prisoners.
"The question is: Was the CIA really working in Europe?" Marty was quoted as saying by the Associated Press. "I believe we can say today, without a doubt, that the answer is yes."
The Council of Europe, based in Strasbourg in France, began its investigation after allegations surfaced in November that US agents interrogated key al-Qaeda suspects at clandestine prisons in eastern Europe and transported some suspects to other countries via Europe.
New York-based Human Rights Watch identified Romania and Poland as possible sites of secret US-run detention facilities. Both countries have denied any involvement.
Marty's comments come in the same week that the publication by a Swiss newspaper of a secret document on alleged CIA prisons in eastern Europe caused an uproar in Switzerland.
Criticism of Europe
Marty said that European countries had been "complicit" in the CIA's alleged activities.
"It's not possible to transport people from one place to another in such a manner without the secret services knowing about it," he was quoted on Reuters. "What was shocking was the passivity with which we all, in Europe, welcomed these things."
He said Europeans should be less hypocritical and not turn a blind eye. "There are those who do the dirty work abroad, but there are also those who know when they should close their eyes when that dirty work is being done."
The parliamentarian, a former Ticino state prosecutor, referred to the case of an Egyptian cleric alleged to have been kidnapped by the CIA in Milan in 2003 and transported to Egypt, where the man later said he was tortured.
A Milan court last month issued a European arrest warrant for 22 CIA agents suspected of involvement in the case. Italy's government has strongly denied knowledge of the operation.
The Milan case is one of several investigations into whether US agents used Europe to illegally transfer militant suspects to third countries for interrogation.
Marty's comments come after the mass-circulation Sunday newspaper, SonntagsBlick, published a confidential fax last Sunday supposedly confirming the existence of the alleged secret prisons in Europe.
This was sent by Egypt's foreign ministry to the Egyptian embassy in London, but was intercepted by the Swiss intelligence service in November.
The leak has been strongly condemned by the Swiss cabinet. The Federal Prosecutor's Office and military prosecutors are also investigating a possible breach of official secrets by the SonntagsBlick editor and two journalists.
Marty said that he would like a copy of the fax, because it was a "significant element" as it was a "different source".
The Egyptian fax states that 23 Iraqi and Afghan citizens were transferred to a Romanian military base near the port of Constanza for interrogation purposes. It added that similar detention centres had been set up in Ukraine, Kosovo, Macedonia and Bulgaria.
Marty is due to present a preliminary report on the CIA affair to the Council of Europe on January 23. He said that his investigation would probably not be completed for another 12 months as he seeks more evidence.
swissinfo with agencies
Swiss parliamentarian Dick Marty is head of the Committee on Legal Affairs and Human Rights at the Council of Europe.
He has been appointed head of a Council of Europe inquiry into alleged CIA prisons in Europe.
Marty is due to present a first report on the affair by the end of January.
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