Zintan-based militia releases Saif al-Islam, the son of Muammar Gaddafi, who was toppled in 2011 uprising.

Saif al-Islam Gaddafi, the son of slain Libyan leader Muammar Gaddafi, has been released from prison, according to fighters who control the facility.

A statement from the Abu Bakr al-Siddiq Battalion, a militia which controls Zintan, a mountainous region southwest of the capital Tripoli, said Saif al-Islam was released late on Saturday.

“The armed group has issued a statement on its Facebook page saying that it has recently released Saif al-Islam Gaddafi upon request from the House of Representatives (HoR), the parliament that is based in the eastern city of Tobruk,” Al Jazeera’s Mahmoud Abdelwahed, reporting from the capital, Tripoli, said.

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Since Muammar Gaddafi’s four-decade rule ended in 2011, Libya has struggled to establish basic institutions and rule of law.

The Tobruk-based HoR is one of the three rival administrations in Libya – the others being the UN-backed government of National Accord (GNA) in Tripoli, which has struggled to exert its authority, and the self-declared National Salvation Government, also in the capital.

HoR, which does not recognise the other two governments’ leadership, is backed by renegade General Khalifa Haftar.

“We understand that a couple of days ago, a deputy justice minister of the government affiliated to the Tobruk-based parliament visited Saif al-Islam Gaddafi in the jail in Zintan and demanded his immediate release,” said Abdelwahed.

“There has been no official comment from the GNA, and the news of the release of Saif al-Islam Gaddafi might add more fuel to the fire, [worsening] the chaotic political and security situation in the country,” he added.

The most prominent of Gaddafi’s sons, Saif al-Islam, 44, was captured in Zintan in November 2011 as he was fleeing to neighbouring Niger after opposition fighters seized Tripoli.

He was sentenced to death in July 2015 by a court in Tripoli in a mass trial of former Gaddafi government officials.

He is wanted by the International Criminal Court on charges of war crimes and crimes against humanity.

The commander of the Abu Bakr al-Siddiq Battalion, Ajmi al-Atiri, was set to release a video statement explaining the details of the release.