A US judge has ruled that a copy of an alleged confession by the Libyan accused of building the bomb that downed Pan Am Flight 103 over Lockerbie can be used in his trial. Abu Agila Mas'ud Kheir Al-Marimi, 74, is set to face trial in April. His lawyers had argued the alleged confession should be inadmissible because it was not the original document and that Al-Marimi was forced to make it under duress by masked men while in custody in Libya.

Judge Dabney Friedrich denied the motion, allowing the confession to be used as evidence. Al-Marimi, who appeared in court wearing a green prison jumpsuit and listened through an interpreter, has denied building and priming the bomb that killed 270 people on December 21, 1988.

Al-Marimi claims he was coerced into memorizing details about the destruction of Pan Am 103 and another terror attack, and was forced to repeat them to a Libyan official under threat to his family. He also alleges his removal from Libya to face trial in the United States was an "illegal cloak and dagger operation."

Details of the alleged confession first surfaced five years ago when the US Department of Justice charged Al-Marimi. An FBI summary of a criminal complaint claimed he admitted playing a key role in the attack during detention in 2012, after the collapse of Colonel Muammar Gaddafi's regime. The FBI states that the Libyan official who recorded Al-Marimi's confession in 2012 is prepared to testify at the trial.

Of the 270 people killed in the bombing, 190 were American citizens. The trial will take place in the United States. The only previous Lockerbie trial occurred from May 2000 to January 2001, resulting in the conviction of Libyan intelligence agent Abdulbasset al-Megrahi for his key role in the plot. Al-Megrahi was sentenced to life in prison but released on compassionate grounds in 2009 after being diagnosed with terminal cancer. He died in Tripoli three years later.

A mugshot of Abu Agila Mas'ud Kheir Al-Marimi. He has a white beard and is staring straight ahead. He is wearing a prison overall of some form.