WASHINGTON, United States (AFP) — A US military judge ruled Friday that confessions made by alleged 9/11 attacks mastermind Khalid Sheikh Mohammed to Federal Bureau of Investigation (FBI) agents are inadmissible and cannot be used against him at trial, The New York Times reported.

The ruling comes just before the 25th anniversary of the 11 September 2001 attacks that killed nearly 3,000 people in New York, Washington and Pennsylvania.

This week, the trial date for Mohammed and three others accused plotters was set for 5 June 2028 at the US naval base in Guantanamo Bay, Cuba.

Mohammed, also known as “KSM,” was considered one of Al-Qaeda leader Osama bin Laden’s top lieutenants before he was captured in March 2003 in Pakistan.

Prosecutors have already excluded statements that Mohammed made after his capture when he was held by the Central Intelligence Agency in overseas prisons and subjected to brutal treatment including waterboarding before his transfer in 2006 to Guantanamo, the Times reported.