Abu Hamza appears in court in New York without his hook - Telegraph.co.uk
The accused were "at the nerve centres of Al Qaeda's 'terror networks' and will finally face justice", said Preet Bharara, the US district attorney who will lead the prosecution in New York.
Hamza, 54, an Egyptian-born naturalised Briton who once worked as a London nightclub bouncer, is being held in the maximum-security "terror wing" of the Metropolitan Correctional Centre (MCC) with Adel Abdel Bary, 52, and Khaled al Fawwa, 50.
He was led through a tunnel under the street to the federal courthouse in lower Manhattan for his first appearance before a magistrate on Saturday.
Hamza faces terrorism charges for the 1998 kidnapping in Yemen of Western tourists in which three Britons and an Australian were killed, supporting the establishment of a terrorist training camp in Oregon and facilitating violent jihad in Afghanistan.
Bary and Fawwaz are also charged with participation in the bombings of two US embassies in east Africa in 1998 that killed 224 people, including 12 Americans. Among the defendants on that charge sheet is the late Osama bin Laden, the former al-Qaeda chief.
Two other defendants, Syed Talha Ahsan, 33, and Babar Ahmad, 36, who are both British, pleaded not guilty at a separate appearance in US District Court in New Haven, Connecticut, on Saturday morning.
They are charged with operating websites that sought to raise cash and equipment and recruit fighters for al Qaeda and for terrorist groups in Afghanistan and Chechnya.
Mary Galligan, head of the FBI in New York, added "The extraditions of Abu Hamza, Bary and Fawwaz are a major milestone in our effort to see these alleged high-level terrorists face American justice. The indictments allege the direct participation of these defendants in planning and carrying out some of the most odious acts of al Qaeda terrorism."
In the 1990s, Hamza turned the Finsbury Park mosque into a recruiting ground Islamic radicals. Among congregation for his hate-filled anti-Western sermons were Sept 11 conspirator Zacarias Moussaoui and failed "shoe bomber" Richard Reid, who are both serving life sentences in the solitary confinement in the "Supermax" in Colorado.
Lawyers for Hamza, who described al Qaeda founder Osama bin Laden as a "hero", had fought a long battle against his extradition, arguing that he suffered from depression, chronic sleep deprivation, diabetes and other ailments.
They and lawyers for the other four men argued that the threat of indefinite solitary imprisonment in such harsh conditions in the US was "inhumane" under European statutes.
But European judicial authorities finally rejected their cases and on Friday, the High Court in London ruled that the men had run out of grounds for appeal and could be extradited immediately.
"I'm absolutely delighted that Abu Hamza is now out of this country," British Prime Minister David Cameron said. "Like the rest of the public I'm sick to the back teeth of people who come here, threaten our country, who stay at vast expense to the taxpayer and we can't get rid of them."
"I'm delighted on this occasion we've managed to send this person off to a country where he will face justice," he added.
Hamza, the son of an Egyptian army officer who gained British nationality by marriage, had previously been convicted in London on separate charges of inciting racial hatred and encouraging followers to kill non-Muslims.
The extradition of Ahmed caused particular controversy as his alleged crimes were committed in Britain but British courts declined to prosecute him for lack of evidence. He is facing charges in Connecticut because as an Internet service provider there was allegedly used to host one of the websites.
The court had earlier ruled that the conditions at "Supermax" do not amount to torture, a key plank of the accused men's attempts to fight extradition under the European Court of Human Rights.
Due to his poor health, it is thought Abu Hamza may be sentenced to serve a jail term in another high-security facility. But if convicted, the other four are expected to be sent to Supermax.
Under the terms of the extradition deal, they cannot face the death penalty or be sent the Guantanamo Bay prison camp for prosecution at a special military tribunal. They must be tried in a federal civilian courts.
It could take anywhere from nine months to two years before the men face a full trial. They will initially be defended by court-appointed lawyers, but there is an experienced group of attorneys who have represented Guantanamo detainees who may be interested in taking their cases.
US legal analysts said the men might be advised to strike plea bargains and receive sentences in the region of around 15 years for co-operating with prosecutors.
The Manhattan Federal Court where Hamza was scheduled to appear yesterday is a tall, imposing stone building located in downtown New York which has dealt with some of the most high profile cases in recent history, including disgraced financier Bernie Madoff.
Three police officers stood outside the court wearing bullet proof vests and armed with guns. Crowd control barriers had been put out the front of the building.
Hamza is expected to be held awaiting trial at the Metropolitan Correctional Centre in near solitary confinement in the prison's "special housing unit". The MCC is a grim, fortress-like structure, standing 14 stories tall and made of concrete that has stained over the years.
Previous terror suspects held there have been kept in solitary for 23 hours a day and 24 hours on weekends.
Even during Hamza's hour out of his cell he is unlikely to see anyone else and will instead be allowed to exercise in the caged area on the roof for an hour a day on his own
Lawyers for convicted arms trader Viktor Bout, who spent 14 months there in solitary, said it was so vile that it was like the jail depicted in the Alexandre Dumas novel The Count of Monte Cristo. Prison guards are also known to pound on the doors at 2am and 5am and shine their flashlights in to make sure prisoners are still there.
The only TVs are in the common areas which Hamza will probably never be allowed to visit.
The prison holds about 750 inmates, though not all of them will be of the same standing as Hamza and include drug dealers and gangsters.
Among those who have been held at the MCC include mafia crime boss John Gotti, failed Times Square bomber Faisal Shahzad and 1993 World Trade Centre bomber Ramzi Yousef.