Khalid Sheikh Mohammed, the alleged mastermind of the 9/11 attacks, has pleaded guilty to all the charges in connection with his role in the 2001 attack. He also told a US military court on Thursday that he wanted to become a martyr.

Earlier, Mohammed refused to appoint a lawyer and told the judge that he wanted to represent himself, according to a CNN report.

When the judge asked Mohammed if he understood that he faces the death penalty, he said, "That is what I wish. I wish to be martyred," states the report.

Mohammed told the court that he did not want a lawyer to represent him as it was against the Sharia or the Islamic law.

Mohammed and his four co-defendants, all allegedly members of al Qaeda, are being tried on various charges for their alleged roles in the September 11, 2001, terror attacks,  which killed nearly 3,000 people.

The report states that the defendants have been in custody since 2002 and 2003, and they were transferred to Guantanamo Bay in September 2006.

Earlier, Mohammed had said in a written statement that he was responsible for the attacks 'from A to Z', according to CNN.