Seif al-Islam Gaddafi, the son and once seen as successor of Libya’s late dictator Muammar Gaddafi, has been killed in the northern African country, Libyan officials announced Tuesday.

The 53-year-old man was killed in the town of Zintan, 136 kilometers southwest of the capital Tripoli, Libya’s Chief Prosecutor’s Office said.

The agency said in a statement that an initial investigation had determined that Seif al-Islam had been shot to death, but did not provide further details about the circumstances of the killing.

Seif al-Islam’s lawyer, Khaled al-Zaidi, confirmed his death on Facebook, without providing further details.

Abdullah Osman Abdulrahim, who represented Gaddafi in the United Nations-mediated political dialogue aimed at resolving Libya’s long-running conflict, also announced his death on Facebook.

Seif al-Islam’s political team later issued a statement saying “four masked men” stormed his home and killed him in a “despicable and dangerous assassination”. After a confrontation with the attackers, the statement said, the attackers closed the home’s surveillance cameras “in a desperate effort to cover up the traces of their heinous crime.”

Seif al-Islam was born in Tripoli in June 1972, the second son of a longtime dictator. He studied for a Ph.D. He studied at the London School of Economics and was considered the reformist face of Gaddafi’s regime.

Muammar Gaddafi was overthrown in a NATO-backed uprising in 2011 after more than 40 years in power. He was killed in October 2011 during the ensuing fighting that escalated into civil war. Since then, the country has been in turmoil, split into rival armed groups and militias.

Seif al-Islam was captured by militants in Zintan in late 2011 as he tried to flee to neighboring Niger. The fighters released him in June 2017 after one of Libya’s rival governments granted him amnesty. Since then, he lived in Zintan.

A Libyan court convicted him of inciting violence and killing demonstrators and sentenced him to death in absentia in 2015. He was also wanted by the International Criminal Court for crimes against humanity related to the 2011 riots.

In November 2021, Seif al-Islam announced his candidacy for the country’s presidential elections in a controversial move that drew protests from anti-Gaddafi political factions in western and eastern Libya.

The country’s senior national electoral commission disqualified him, but elections were not held because of the conflict between rival regimes and armed groups that have ruled Libya since the bloody ouster of Muammar Gaddafi.