A terror suspect once arrested in connection with a possible ricin plot against Britain has launched an appeal against a government bid to deport him.
Home Secretary Charles Clarke wants suspect Y to be deported
The Algerian, known only as Y, was cleared last year of conspiring to use ricin but the government maintains he is a threat to national security.
Y says sending him back to Algeria would breach his human rights.
But claims he would be in danger were not backed up, the Home Office told the Special Immigration Appeals Commission.
'Terror group connections'
Ian Burnett QC, for the home secretary, told a London hearing Y had "extensive Islamic extremist connections".
He said Y was in fact the leader of the UK branch of the DHDS - an Algerian terrorist group which aims to unite disparate Islamic extremist groups - this is denied by Y.
He may have trained in Afghanistan and had been found to have "significant numbers" of false documents, the tribunal was told.
He had "close links" with north London's Finsbury Park mosque, where he was often trusted with the keys and did the photocopying, the government lawyers claimed.
Campaigners argue that this is the first appeal against deportation to a country where it is accepted that a person would be at risk of torture or death.
Under human rights laws suspects cannot be deported to countries where they may face abuse.
But Mr Burnett told the hearing there were no substantial grounds for believing that Y would be at risk of torture on his return to Algeria and that the appeal should be dismissed.
It comes a day after Amnesty International published a report highlighting a series of torture techniques used by Algeria's military intelligence service, the DRS.
Britain is seeking to sign a "memorandum of understanding" with Algeria, aiming to guarantee that anyone returned there would not be ill-treated.
The level of risk Y would face if deported is "very low", Mr Burnett said.
Y was alerted that a deportation order was being sought against him on 15 September, 2005.
Along with four other potential Algerian deportees, his terms of conditional bail were varied in January to allow him to visit the Algerian consulate to talk to the authorities about a voluntary return.
Another four Algerians have since withdrawn their appeals and are set to return voluntarily to their homeland, the tribunal was told.
Y arrived in Britain on a false French passport in March 2000. He claimed asylum, showed his genuine passport and was granted indefinite leave to stay in June 2001.
Despite his denials of being a senior figure in the DHDS movement, his arrest in January 2003 over the alleged ricin plot was quickly reported back to the DHDS command in Algeria, Mr Burnett told the hearing.
False documents and a DHDS audiotape were found at Y's home and his fingerprints were on documents at the heart of the terrorist ricin plot, Mr Burnett added.
Y, who was cleared on conspiracy along with three others at the Old Bailey, claims his fingerprints were found through "innocent association" because of his job at the mosque.