HUMAN rights groups are backing calls to investigate alleged CIA transfers of terror suspects through Biggin Hill airport.

The American intelligence agency has allegedly used 19 UK airports since the September 11 attacks, to transfer prisoners to countries where torture is common, such as Egypt.

US Secretary of State Condoleezza Rice has subsequently denied the agency has transported any terror suspects through Britain.

However, according to figures gathered by a national newspaper from US Federal Aviation Administration flight logs, at least 11 flights have passed through Biggin Hill.

On Monday, a group of American legal experts, commissioned by an all-party group of MPs, said it believes the British Government has broken the law by allowing the flights to touch down.

Under the process known as extraordinary rendition, the suspects are denied legal representation and taken to secret detention centres.

A call by the human rights group Liberty for Met Police to investigate has been backed by peace organisations.

The group alleges the CIA has breached the Criminal Justice Act which forbids torture anywhere in the world.

By allowing the touchdowns the British Government had played a part in the torture.

Orpington resident Sheila Triggs, who is president of the Women's International League for Peace and Freedom, says the revelations are both "shocking" and "morally abhorrent".

And Ann Garrett, secretary of Bromley and Beckenham Campaign for Nuclear Disarmament (CND) said: "I'm outraged our local airport may have been used for such flights.

"Private companies should be accountable to local councils and the public by providing information."

There is nothing to suggest the airport is guilty of any wrongdoing.

A Biggin Hill Airport spokesman said: "The Airport is a port of entry and has full customs and immigration facilities throughout the opening hours. A flight such as that would have been brought to our notice. We are not aware of the type of flight reported being operated at this airport.

More than 300 flights operated by the CIA have passed through UK airports.