The lead European investigator looking into allegations that Poland and Romania hosted secret CIA prisons said Monday that neither government has responded to calls for their own inquiries into the matter.

Swiss Senator Dick Marty implicated the two countries in a report last month as possibly having hosted the secret detention centers for terrorism suspects in the past. Both countries have denied the allegation.

Marty, investigating on behalf of the Council of Europe human rights watchdog, offered no clear, direct proof in his report that CIA detention centers were set up there — an allegation made by a human rights group last year. Instead he relied on circumstantial evidence based on flight logs provided by the European Union air traffic agency.

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In his report, Marty alleged European nations aided the movement of 17 detainees who said they had been abducted by U.S. agents and secretly transferred to detention centers around the world. Some said they were transferred to the U.S. detention facility at Guantanamo Bay, Cuba, and others to alleged secret facilities in countries including Poland, Romania, Egypt and Jordan. Some said they were mistreated or tortured.

Marty and the EU's top justice official, Franco Frattini, have both called for immediate domestic probes in Poland and Romania into CIA activities there and the two countries' governments possible collusion in human rights violations.

"We have not received a single response, single information that these inquiries have been carried out," Marty told the European Parliament committee that carries out a parallel investigation into the allegations.

Marty's report was slammed by Polish members of the European Parliament, who said Thursday it was based on hearsay and offered no proof of any wrongdoing.

Poland and Romania have said they carried out internal investigations when the allegations surfaced in November. But details of the investigations — both lasting just a few weeks — were never made public.