Amnesty International today revealed that six planes used by the CIA for renditions have made some 800 flights in European airspace including 50 landings at Shannon airport in the Republic of Ireland.

The information contradicts assurances given last week by the US Secretary of State Condoleezza Rice to the Irish Foreign Minister Dermot Ahern, that Ireland's Shannon airport had not been used for "untoward" purposes, or as a transit point for terror suspects. Amnesty International also rejected fresh assertions by the US Secretary of State as she began a four-nation tour of Europe.

In a statement today, Ms Rice argued that rendition - transferring detainees from country to country without legal process - was permissible under international law.

Although the victims of rendition usually end up in countries known to use torture in their interrogations, Ms Rice added that the US government seeks assurances over treatment from receiving nations. This follows newspaper reports at the weekend of such flights landing in Scotland.

Amnesty International Scotland Programme Director Rosemary Burnett said: "Flying detainees to countries where they may face torture or other ill-treatment is a direct and outright breach on international law with or without so called 'diplomatic assurances'.

"These assurances are meaningless. Countries known for systematic torture regularly deny the existence of such practices."

Amnesty international has obtained flight records for six CIA-chartered planes from September 2001 to September of 2005. According to the US Federal Aviation Administration over this period, these planes landed 50 times in Shannon and took off 35 times, suggesting that some flights were kept secret. Although Shannon airport is used as a re-fuelling stop for the US military, none of the planes were military transport planes. In total for this period, the six planes made some 800 flights originating or landing in Europe.

The planes include: * Boeing 737-7ET, call sign N313P (later re-registered as N4476S). The largest of the six planes, with 32 seats, is owned by Premier Executive Transport Services, a CIA front company that also owns N379P. N313P has been frequently seen at US military bases, including in Afghanistan. * Gulfstream V: call sign N379P (later re-registered as N8068V and then as N44982). This plane, which has made more than 50 trips to the US detention centre in Guantanamo Bay, has been nicknamed 'The Guantanamo Bay Express'. It was also used in the CIA rendition of Ahmed Agiza and Mohammed al-Zari from Sweden to Egypt. * Gulfstream III: N829MG (later re-registered as N259SK). This plane took dual Syrian-Canadian national Maher Arar from the US to Syria where he was detained for over a year without charge, during which time he was tortured. He was finally released in October 2003. * Gulfstream IV, call sign N85VM (later re-registered as N227SV). This plane took Abu Omar to Egypt from Germany after his kidnapping in Italy, turned around and flew to Shannon.

The plane's flight log also shows visits to Afghanistan, Morocco, Dubai, Jordan, Italy, Japan, Switzerland, Azerbaijan and the Czech Republic. Amnesty International is publishing the information after a challenge by the Irish Foreign Minister Dermot Ahern on Thursday last week. Asked about CIA planes using Shannon airport, the Foreign Minister said: "If anyone has any evidence of any of these flights please give me a call and I will have it immediately investigated."

On 17 Feb 2003, for instance, the Gulfstream IV, N85VM took Abu Omar from Ramstein to Cairo, then turned around and flew to Shannon, arriving at 0552 on the 18th. The latest information confirms other persistent and reliable reports in the media and by non-governmental organisations that CIA-chartered flights are used for renditions. Amnesty International only has partial flight logs for six planes whilst the CIA has been reported to use some 30 leased aircraft.

European countries have allowed these aircraft to land, refuel and take off from their territory. Under international law and standards, all states must cooperate to bring to an end any serious breach of the prohibition of torture and other peremptory rules of international law. They must also refrain from aiding or assisting those carrying out such breaches. Amnesty International calls on European countries to investigate promptly and thoroughly allegations that their territory has been used to assist CIA-chartered flights secretly transporting detainees to countries where they may face "disappearance", torture or other ill-treatment.

Pending the results of such an investigation, all countries must ensure that their territory and facilities are not used to assist rendition flights. Amnesty International is urging all member States of the Council of Europe to provide full cooperation with the investigation being carried out by the Parliamentary Assembly of the Council of Europe on allegations about secret detention centres, and provide complete information on their internal law and practices relating to secret rendition flights, as requested by the Secretary General of the Council of Europe.