A former Croydon student and father will play a key role in the trial of "terror suspect" Abu Hamza in New York tomorrow.
Feroz Ali Abbasi, 34, was born in Uganda before moving to Croydon with his mother in 1988 and becoming a UK citizen.
He was one of the nine Guantanamo Bay inmates in the US who was supported by Amnesty International.
The charity insists the Americans have been unable to bring any evidence against him.
He was captured in Afghanistan and detained in the notorious prison from December 2001 to January 2005.
Abbasi claims he moved to Afghanistan to continue his studies in Islam and was trying to escape the fighting between the Taliban and Nato forces when he was captured.
Now he is being bought into the trail of Abu Hamza, accused of being a "terrorist leader of global reach" who was sent to Al-Qaeda camps with Hamza for jihad training in 2001.
Prosecutors in the Hamza case are arguing the evidence is central to proving Hamza sent his followers to military Al-Qaeda training.
Hamza became infamous in the UK as the preacher at Finsbury Park mosque who was convicted of inciting hatred and jailed for seven years in 2006.
The US then organised his extradition so he could be tried on terror-related charges which he faces next week.
Amnesty International have used Abbasi's case to campaign for Guantanamo's closure, arguing the detainee was incarcerated without trial or charges.
The Americans claim Abbasi taught assassinations and surveillance as well as fighting with Taliban and Al-Qaeda forces in Afghanistan.
Although he "confessed" at a tribunal in Guantanamo in 2004 to fighting with the Taliban, he later said it was written under the influence of drugs forced on him by medics and that he never fought against Nato troops in Afghanistan.
He was released in 2005 and returned to Croydon where he got married, became a father and went to a London university.
He has also worked with the charity Cage which supports Muslim prisoners detained as "part of the war on terror".
Prosecutors in the Hamza case hope to bring a witness - Saajid Badat - to court so he can testify against the defendant and Abbasi.
Mr Badat is said to claim Abbasi was a "terror lieutenant" who planned to attack American and Jewish targets.
However, Mr Badat will be forced to give evidence via video-link from London as he refuses to travel to the US where he faces arrest over the failed "shoe bomb" plot in 2001.
