Khalid Shaikh Mohamed, the alleged mastermind behind the attacks of September 11, has offered to plead guilty in a Guantanamo Bay courtroom, as have his four co-defendants.
Mr. Mohammed, accused of being the principal architect of the attacks, is one of five co-accused in what is by far the most important case here.
Mr. Mohammed, Walid Bin Attash, Ramzi Bin al Shibh, Ali Abdul Aziz Ali and Mustafa al Hawsawi all face the possibility of execution. Mr. Mohammed, Mr. Attash and Mr. Bin al Shibh have chosen to represent themselves.
Today's court proceedings were scheduled to begin with the first of a flood of motions to dismiss the charges against the men based on various legal issues, such as whether the charges against them are recognizable under the law of war.
However, that all came to a halt Monday morning, when it was announced that the defendants had no interest in pursuing any of those motions.
"[The accused wish]to enter pleas in what was termed as confessions in this case," the presiding judge, U.S. Army Colonel Stephen Henley, said.
Col. Henley said he had received a letter from the five men offering to confess in full to the crimes they are charged with.
When asked by the judge whether he was prepared to enter a guilty plea today, Mr. Mohamed said yes, adding that he had no intention of wasting the judge's time.
While the joint guilty pleas came as some surprise, the men are still a long way from being sentenced. The judge is expected to investigate further the reasons behind the pleas.
But even if the pleas are accepted, it is unclear what impact they will have if the incoming Obama administration decides to shut down the military commissions system upon taking office in late January.
This was the first time in the history of the Guantanamo Bay military commissions that relatives of those who died in the 9/11 attacks were allowed to attend court proceedings. The relatives were separated from the rest of the observers - mainly journalists - by a blue curtain.
Human rights groups monitoring the proceedings here quickly condemned today's developments, saying they could not be considered legitimate given that the men on trial had previously been tortured while in U.S. custody.
"What should have been a major victory in holding the 9/11 defendants accountable for terrible crimes has been tainted by torture and an unfair military commissions process," said Jennifer Daskal, senior counterterrorism counsel at Human Rights Watch, in a statement. "These five men are known to have been mistreated and tortured during their years in CIA custody, including the acknowledged water boarding of Khalid Sheikh Mohammed."
Editor's Note: An earlier online version of this story indicated 9/11 victims' relatives in attendance used laptops during the proceedings. This version has been corrected.