- 270 people were killed when Pan Am Flight 103 exploded over the Scottish town in 1988
- Scotland's chief public prosecutor has written to Libyan authorities asking for assistance
They have asked for Libya's help to interview them.
The 259 people on New York-bound Pan Am Flight 103 and 11 people on the ground were killed when it crashed 38 minutes after takeoff from London on December 21, 1988.
Afterward, U.S. and British investigators found fragments of a circuit board and a timer and ruled that a bomb, not mechanical failure, caused the explosion.
Libyan Abdelbeset Ali Mohmed al Megrahi
was the only person convicted in connection with the bombing.
Two named suspects
Scotland's prosecution service, the Crown Office
, on Thursday said Scotland's chief public prosecutor -- known as the lord advocate -- and the U.S. attorney general had recently agreed there was a legal basis for Scottish and U.S. investigators to treat two Libyans as suspects in the bombing.
The lord advocate has issued an International Letter of Request
to the Libyan attorney general in Tripoli identifying the pair, it said in a statement.
"The Lord Advocate and the U.S. Attorney General are seeking the assistance of the Libyan judicial authorities for Scottish police officers and the FBI to interview the two named suspects in Tripoli.
"The two individuals are suspected of involvement, along with Abdelbaset Ali Mohmed Al Megrahi, in the bombing of flight Pan Am 103 in December 1988 and the murder of 270 people," the statement said.
Al Megrahi was found guilty in 2001 of the murders of those on board the plane and on the ground.
In August 2009, he was released from a Scottish prison on the grounds that he had been diagnosed with terminal prostate cancer and had only a few months to live. He was sent home to Libya on "compassionate" grounds, receiving a hero's welcome at the airport, and died in 2012.
Libya agreed in 2003 to pay $2.7 billion in compensation to the families of the bombing victims, though Libyan leader Moammar Gadhafi always remained cagey about admitting official Libyan involvement in the bombing.