The new charges follow decades of work by Justice Department leaders aimed at investigating and prosecuting those responsible for 270 deaths.

Transcript

MARY LOUISE KELLY, HOST:

Thirty-two years ago today, an airliner blew up over Lockerbie, Scotland, killing all the passengers and 11 other people on the ground. The bombing of Pan Am Flight 103 remains the deadliest single terrorist attack in the United Kingdom. U.S. Attorney General Bill Barr helped lead that investigation during his earlier stint in government. And today, his last week on the job, he announced new charges in the case. NPR's Carrie Johnson reports.

CARRIE JOHNSON, BYLINE: On December 21, 1988, hundreds of passengers boarded an airplane, including American college students returning home from a study-abroad program to spend Christmas with their families. They never made it. Attorney General Bill Barr.

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WILLIAM BARR: The massive Boeing 747, known as the Clipper Maiden (ph) of the Seas, exploded and fell to the ground in countless pieces, scattered across 840 square miles, nearly the entire width of Scotland.

JOHNSON: American law enforcement officials worked hand in hand with their counterparts in Scotland to investigate the crime - conducted more than 10,000 interviews, combed through bright green fields covered with small bits of plastic and shredded clothes.

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BARR: What they did, lining up police officers and literally looking at every blade of grass in that footprint, was astounding.

JOHNSON: In that grass, they found a piece the size of a thumbnail, part of the cassette player that contained the bomb. Authorities pinned the blame on the Libyan government. Two men were brought to justice, but only one was convicted. He served several years in prison before winning compassionate release and dying three years later. Today, Barr told reporters in Washington the case represented unfinished business, business he wanted to close before leaving the Justice Department this week.

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BARR: I am pleased to announce that the United States has filed criminal charges against a third conspirator, Abu Agela Mas'ud Kheir Al-Marimi.

JOHNSON: Barr said the man, known for short as Mas'ud, was a longtime member of the Libyan intelligence service. He's accused of terrorism charges, including destruction of an aircraft resulting in death. Authorities cited travel records and other circumstantial evidence linking Mas'ud to the tragedy in the skies above Lockerbie. But they said the tipping point came when Libyan officials interviewed Mas'ud and provided the U.S. with a transcript. Michael Sherwin is acting U.S. attorney in Washington, D.C.

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MICHAEL SHERWIN: Statements from Mas'ud in which he talks about his role in the bombing, making the bomb, and also the role with the co-conspirators.

JOHNSON: Prosecutors are hoping the Libyans will send Mas'ud to the U.S. to face justice.

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KARA WEIPZ: We have always been assured that this was an open case and no lead would be unfollowed. Today is the culmination of that hard work.

JOHNSON: Kara Weipz's brother Rick died on Pan Am Flight 103. She now leads a group for victims' family members.

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WEIPZ: Today confirms what we believe to be true and a step forward in holding all those responsible for the murders of 270 innocent people on this day.

JOHNSON: For the attorney general, the event marks what could be his last public appearance in government. Barr leaves the Justice Department this week. His departure follows a disagreement with President Trump over appointing a special counsel that would investigate Trump's baseless claims of widespread election fraud.

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BARR: If I thought a special counsel at this stage was the right tool and was appropriate, I would name one. But I haven't, and I'm not going to.

JOHNSON: Barr also mentioned the Justice Department tax investigation into President-elect Joe Biden's son, Hunter. He said it's being handled professionally and there's no need for a special counsel there, either. As for his rocky return to public service, when he drew criticism for shielding the president from investigations and lawsuits, Barr said he has no regrets.

Carrie Johnson, NPR News, Washington.

(SOUNDBITE OF PHIL FRANCE'S "THE SWIMMER") Transcript provided by NPR, Copyright NPR.