The first of four Algerian terrorist suspects to agree to be deported has left the UK, the Home Office said today.
The Government said it intended to deport the other men - who have been held in Britain without trial under controversial anti-terror powers - "as soon as possible".
Some of the Algerians have spent five years in prison in the UK without charge, according to human rights lawyer Gareth Peirce, whose firm is representing three of them.
A Home Office spokeswoman said: "An Algerian national who had been identified as representing a threat to the national security of the UK was yesterday deported to Algeria.
"This is not the first time that we have removed suspected international terrorists to Algeria - two were returned in June 2006.
"Other Algerian nationals have also withdrawn their appeals and it remains our intention to deport them as soon as possible.
"A number of others are appealing against their deportation and their cases are currently before the Special Immigration Appeals Commission."
Ms Peirce condemned the Government's policy of locking up terror suspects without trial.
The four men feared detention and torture in their country of birth but had chosen a "quick death there rather than an endless slow death here", she said.
In June last year two Algerian men suspected of being international terrorists were voluntarily removed from Britain after dropping appeals against Government deportation moves.
The pair - who could only be identified as "Mr I" and "Mr V" - - were both former "Belmarsh detainees".
Mr V was acquitted in April 2005 of involvement in a plot to poison Londoners with the toxin ricin.
Mr I, who was alleged to be a senior member of the Abu Doha terror group, was imprisoned without charge or trial for three years under the Government's Internment Powers.
The Home Office has struggled for years over what to do with terror suspects.
Internment laws brought in after the September 11 terror attacks in the United States were knocked down by the Law Lords and the replacement control order regime has also been criticised.
Ministers were unable to forcibly deport people like Mr I and Mr V to Algeria because human rights laws say they cannot be returned to a country where they may face torture or ill-treatment.