The Lockerbie bombing suspect was taken into custody on Sunday. 

"The United States has taken custody of alleged Pan Am flight 103 bombmaker Abu Agila Mohammad Mas’ud Kheir Al-Marimi," a Department of Justice spokesperson confirmed to WHD News. "He is expected to make his initial appearance in the U.S. District Court for the District of Columbia. Additional details, including information regarding public access to the initial appearance, will be forthcoming."

The statement gave no information on how Mas'ud came to be in U.S. custody.

Scotland’s Crown Office and Procurator Fiscal Service said in a statement that "the families of those killed in the Lockerbie bombing have been told that the suspect Abu Agela Mas’ud Kheir Al-Marimi is in U.S. custody." 

DOJ ANNOUNCES CHARGES AGAINST LOCKERBIE BOMBMAKER, A ‘HIT MAN' FOR QADDAFI

Pan Am flight 103, traveling from London to New York, exploded over Lockerbie on Dec. 21, 1988, killing all 259 people aboard the plane and another 11 on the ground. It remains the deadliest terror attack on British soil.

A police officer walks by the nose of Pan Am flight 103 in a field near the town of Lockerbie, Scotland where it lay after a bomb aboard exploded, killing a total of 270 people, Wednesday, Dec. 21, 1988. 

The U.S. Justice Department announced new charges against Mas'ud in December 2020, on the 32nd anniversary of the bombing.

Families of victims of Pan Am 103 which crashed in Lockerbie, Scotland, due to a terrorist bomb, arrive at JFK Airport, New York, New York, December 21, 1988.  (Allan Tannenbaum/Getty Images)

"At long last, this man responsible for killing Americans and many others will be subject to justice for his crimes," William Barr, the attorney general under the Trump administration at the time, said at a press conference. 

US Attorney General Bill Barr holds a news conference to provide an update on the investigation of the terrorist bombing of Pan Am flight 103 on the 32nd anniversary of the attack, at the Department of Justice December 21, 2020.  (Michael Reynolds-Pool/Getty Images)

In 2001, former Libyan intelligence officer Abdelbaset al-Megrahi was convicted of bombing the flight. He is to date the only person convicted over the attack. He lost one appeal and abandoned another before being freed in 2009 on compassionate grounds because he was terminally ill with cancer.

British Prime Minister Margaret Thatcher with police officers at the wreck of Pan Am Flight 103 after it crashed onto the town of Lockerbie in Scotland, December 22, 1988.  (Georges De Keerle/Getty Images)

He died in Libya in 2012, still protesting his innocence.

A breakthrough in the investigation came when U.S. officials in 2017 received a copy of an interview that Mas'ud, a longtime explosives expert for Libya’s intelligence service, had given to Libyan law enforcement in 2012 after being taken into custody following the collapse of the regime of the country’s leader, Col. Moammar Gadhafi.

Carisa Harris-Adamson, from San Francisco, places a US flag in a wreath placed in memory of her uncle John Cummock, who was on the 1988 Pan Am flight 103 as it was bombed over Lockerbie, during a service to mark the 30th anniversary of the Lockerbie Air Disaster, at the Memorial Garden, Dryfesdale Cemetery, Lockerbie, southwestern Scotland, on December 21, 2018.  (JANE BARLOW/AFP via Getty Images)

In that interview, U.S. officials said, Mas'ud admitted building the bomb in the Pan Am attack and working with two other conspirators to carry it out. He also said the operation was ordered by Libyan intelligence and that Gadhafi thanked him and other members of the team after the attack, according to an FBI affidavit filed in the case.

People identified as some of the family members of those killed in the 1988 bombing of a Pan Am jet over Lockerbie, Scotland, watch a meeting of the United Nations Security Council, September 9, 2003, at UN headquarters in New York.  (STAN HONDA/AFP via Getty Images)

While Mas'ud is now the third Libyan intelligence official charged in the U.S. in connection with the Lockerbie bombing, he would be the first to stand trial in an American courtroom.

Helga Mosey, 19, center, with her family, the Rev John Mosey, right, mother Lisa and brother Marcus. Helga, a talented music student, was among the 259 passengers and crew killed when the plane was blown out of the skies over Lockerbie just 38 minutes after take-off.  She was returning to New Jersey where she was working as a nanny before taking up a place at Lancaster University.  (PA Images via Getty Images)

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The Crown Office in its statement added that "Scottish prosecutors and police, working with U.K. government and U.S. colleagues, will continue to pursue this investigation, with the sole aim of bringing those who acted along with al-Megrahi to justice."

The contributed to this report.