Prosecutors will push for the death penalty in the New York trials of five alleged September 11 plotters including the self-proclaimed mastermind of the attack, the US administration has said.
Attorney General Eric Holder announced that Khalid Sheikh Mohammed and four fellow Guantanamo Bay detainees will be transferred to Manhattan for the legal process, in a federal courtroom just blocks away from where the World Trade Center once stood.
Relatives of British victims caught up in the attack welcomed the development, saying it was a chance to see justice served on those being held accountable for their loved ones' deaths.
Mr Holder said he fully expected prosecutors to seek the death penalty in all five of the cases relating to the 2001 attack in New York.
He also announced that a further five alleged terrorists currently held at Guantanamo Bay, including a major suspect in the 2000 bombing of the USS Cole, will face a military trial.
Bringing Mohammed and others to the US to face a civilian trial is a key part of the White House's plan to close the controversial detention centre in Cuba.
But opponents have argued that treating the men as normal criminal suspects will give them the opportunity to espouse their extremist views in open court. Norman Thompson lost his son, Cantor Fitzgerald stockbroker Nigel Thompson, in the attack on lower Manhattan on September 11, 2001.
Speaking from his Sheffield home, Mr Thompson said: “We will never get closure, the sentence we were handed is for the rest of our lives.
“But if they do try him and find him guilty and say, ‘yes, the death penalty' we wouldn't disagree with that.”
Mohammed has previously admitted to interrogators that he was the architect of the plot that saw close to 3,000 innocent victims killed when two planes were flown into the Twin Towers.
It is alleged that he told agents that he suggested the idea to Osama bin Laden as early as 1996. He went on to fund the attacks, train hijackers and oversee the operation, it is claimed.
He will be tried alongside Waleed bin Attash, Ramzi Binalshibh, Mustafa Ahmed al-Hawsawi and Ali Abd al-Aziz Ali.