Libya’s chief prosecutor has opened an investigation into the extradition of a Libyan national accused of making the bomb that downed Pan Am Flight 103 over Lockerbie, Scotland, in 1988, to the United States. US authorities announced on Sunday that they had arrested former intelligence officer Mohammed Abouagela Masud. The following day he appeared in federal court in Washington DC. and was charged with an act of international terrorism. Speaking to reporters in Tripoli, prosecutor Al-Siddiq Al-Sour said the investigation has been opened after a complaint from Masud’s family that his extradition was not lawful. Al-Sour later confirmed the investigation with the Associated Press, but did not provide further details. Libya and the US have no formal extradition agreement. Masud was kidnapped from his family home in Tripoli by armed men in November, according to a statement issued by his family shortly after the incident. The family blames authorities in Libya’s capital Tripoli for the alleged kidnapping and extradition, it added. Masud’s family have released no official comment since that statement and did not respond to the AP’s request for comment. Torn by civil war since 2011, Libya is divided between the government of the prime minister, Hamid Dbeibah, in Tripoli and a rival government based in eastern Libya headed by PM Fathi Bashagha. In western Libya, militia groups have amassed great wealth and power from kidnappings and their involvement in the country’s lucrative human trafficking trade. The official spokesperson for Libya’s Tripoli government did not respond to a request for comment about the investigation. According to Jalel Harchaoui, a north Africa-focused analyst, a proper investigation into how Masud was taken, detained, and transferred would probably uncover illegal steps. “The investigation is unlikely to take place unless Debibah and his support base grow significantly weaker,” he said. On Tuesday, Bashagha labelled Masud’s extradition illegal and called for the former intelligence officer’s immediate release. The New York-bound Pan Am flight exploded over Lockerbie less than an hour after takeoff from London on 21 December, 1988, killing 259 people onboard and 11 others on the ground when it crashed. About 190 American citizens were on the flight, which was destined for New York. A breakthrough in the decades-long investigation came in 2017 when the US Justice Department received a copy of an interview that Masud, a former explosives expert with Libya’s intelligence services, had given to the north African country’s law enforcement in 2012, while in custody following the collapse of Col Muammar Gaddafi’s decades-long rule. In the interview, US officials said, Masud admitted building the bomb in the Pan Am attack. He also said the operation was ordered by Gaddafi’s intelligence services, according to an FBI affidavit. American authorities in December 2020 announced charges against Masud. At that time, he was in Libyan custody. Masud is the third Libyan intelligence official charged in the US in connection with the Lockerbie attack, but the first to appear in an American courtroom. US officials have not explained how he was taken into their custody.