Human rights group Amnesty International says it has further evidence that eastern European countries may have been involved in secret CIA flights to transport terror suspects to clandestine prisons.

The report, released on Wednesday, provides detailed accounts of the experiences of three Yemeni men who believe they were taken by US authorities to secret prisons following lengthy journeys through different climates and time zones.

The 15,000-word report includes testimony taken in February and March from Muhammad Bashmilah, Muhammad al-Assad and Salah Nasser Salim Ali, also known as Salah Qaru.

Bashmilah said he was detained in Jordan in October 2003 while on a trip to visit his mother. Ali was detained in Indonesia in August 2003 and then flown to Jordan where he was taken into custody. Al-Assad claimed he was detained in Tanzania in 2003. However, none of the three could say with confidence where they were taken next.

In their statements, they described travel times, changing climates, temperatures, and daylight hours in detailed descriptions Amnesty says indicates that they may have been held in eastern Europe.

Black site

The men were allegedly held for 13 months at a so-called "black site," a clandestine facility believed to be run by the CIA, before they were returned to Yemen where they were charged with forging travel documents, Amnesty said.

In a statement released with the report, Amnesty International said new information from the men raised "the possibility that they were held somewhere in eastern Europe or central Asia."

"Their captors went to great lengths to conceal their location from the men; but circumstantial evidence such as climate, prayer schedules, and flight times to and from the site suggest that they may have been held in eastern Europe or central Asia," Anne FitzGerald, a senior advisor with Amnesty, said in the statement.

"But without further information from the US government and European authorities, it's impossible to verify exactly where."

The CIA declined to comment on the report.

The US government has said that the transfer of terror suspects is carried out according to US and international law.

Renditions

The Council of Europe, the continent's top human rights watchdog, is investigating US operated flights sometimes referred to as "renditions" where terror suspects are allegedly transferred to third countries for interrogation.

Amnesty said in its report that the CIA is exploiting a loophole that allows private aircraft to land at foreign airports without having to inform local authorities - unlike government or military planes - and called for inspections of planes suspected of being involved.

Amnesty's branch in the Czech Republic said three planes made a total of 20 landings in the capital Prague as part of the rendition programme.

"We asked the Czech government to make sure that airports in the Czech Republic will not be misused for illegal transfers of people that is in breach of international law," said Martin Kryl, Amnesty's chair of the board in the Czech Republic.

"This practice does not ensure justice nor safety but makes torture possible."

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