From the New York Times

BRUSSELS, April 20 ‘ The European Union’s antiterrorism chief told a hearing on Thursday that he had not been able to prove that secret C.I.A. prisons existed in Europe.

“We’ve heard all kinds of allegations,” the official, Gijs de Vries, said before a committee of the European Parliament. “It does not appear to be proven beyond reasonable doubt.”

But Mr. de Vries came under criticism from some legislators who called the hearing a whitewash. Kathalijne Buitenweg, a Dutch member of Parliament from the Green Party, said that even without definitive proof, “the circumstantial evidence is stunning.”

“I’m appalled that we keep calling to uphold human rights while pretending that these rendition centers don’t exist and doing nothing about it,” she said.

Many European nations were outraged after an article in The Washington Post in November cited unidentified intelligence officials as saying that the C.I.A. had maintained detention centers for terrorism suspects in eight countries, including some in Eastern Europe. A later report by the advocacy group Human Rights Watch cited Poland and Romania as two of the countries.

Both countries, as well as others in Europe, have denied the allegations. But the issue has inflamed trans-Atlantic tensions.

Mr. de Vries said the European Parliament investigation had not uncovered rights abuses despite more than 50 hours of testimony by rights advocates and people who say they were abducted by C.I.A. agents. A similar investigation by the Council of Europe, the European human rights agency, came to the same conclusion in January ‘ though the leader of that inquiry, Dick Marty, a Swiss senator, said then that there were enough “indications” to justify continuing the investigation.

A number of legislators on Thursday challenged Mr. de Vries for not taking seriously earlier testimony before the committee of a German and a Canadian who gave accounts of being kidnapped and kept imprisoned by foreign agents.

The committee also heard Thursday from a former British ambassador to Uzbekistan, Craig Murray, who said: “I can attest to the willingness of the U.S. and the U.K. to obtain intelligence that was got under torture in Uzbekistan. If they were not willing, then rendition prisons could not have existed.” But Mr. Murray, who was recalled from his job in 2004 after condemning the Uzbek authorities and criticizing the British and American governments, told the committee that he had no proof that detention centers existed within Europe.

He said he had witnessed such rendition programs in Uzbekistan, but he seemed to back up Mr. de Vries’s assertion when he said he was not aware of anyone being taken to Uzbekistan from Europe. “As far as I know, that never happened,” he said.

While he was ambassador, Mr. Murray made many public statements condemning the government of President Islam Karimov of Uzbekistan for its poor human rights record.

At the time, the Bush administration was using Uzbekistan as a base for military operations in Afghanistan after the Sept. 11 attacks. Mr. Murray, who has remained an outspoken critic of American and British policy toward Uzbekistan, has since been criticized by Foreign Secretary Jack Straw of Britain for breaching diplomatic protocol.