Dec. 21 (UPI) -- On the 32nd anniversary of one of the most high-profile aviation terrorist attacks in modern history, the U.S. Justice Department filed new charges in the case on Monday.
U.S. Attorney General William Barr announced charges against Libyan national Abu Agela Mas'ud Kheir Al-Marimi, for manufacturing the bomb that was smuggled on board Pan Am Flight 103 on Dec. 21, 1988, which later exploded over Lockerbie, Scotland.
Mas'ud was charged with terrorism-related crimes for the bombing, which killed almost 200 American citizens. He is being held in Libya by the United Nations-backed Government of National Accord, Barr said.
"Let there be no mistake, no amount of time or distance will stop the United States and our Scottish partners in pursuing justice in this case," he said at a news conference Monday.
Barr said the key breakthrough came when the United States learned that Libyan officials were holding Mas'ud. They provided U.S. investigators with statements from he made indicating his involvement in the Lockerbie bombing.
"At long last this man responsible for killing Americans and many others will be subject to justice for his crimes," Barr said, adding that Mas'ud built the bomb and worked with two co-conspirators from a base in Malta.
Barr said he's "optimistic" Libyan officials will agree to extradite Mas'ud to the United States to stand trial.
The midair explosion killed 259 passengers and crew and another 11 people on the ground in Lockerbie, a small town in eastern Scotland.
Flight 103 originated in Frankfurt, Germany, with a Boeing 727 but switched to a 747 at London's Heathrow Airport, where it picked up more passengers, many carrying Christmas presents. Its final destination was Detroit.
Barr had ordered an investigation into the bombing in the late 1980s when he worked in the Justice Department under former President George H.W. Bush.
The only person ever held liable for the Lockerbie bombing was Abdel Basset Ali al-Megrahi, a Libyan intelligence officer who was convicted as an accomplice in 2001. he was granted a compassionate release eight years later and died in 2012.