Who is Saif al-Islam Gaddafi?

The most prominent son of slain Libyan leader Muammar Gaddafi has been released from prison according to a statement released by the Abu Bakr al-Siddiq Battalion in Libya's Zintan. The statement did not disclose his current location due to fears for his safety.

Saif al-Islam Gaddafi, 44, was released on Saturday after he was captured and imprisoned by fighters from Zintan while attempting to flee the country to neighbouring Niger back in 2011 when opposition fighters seized Tripoli.

His release comes as part of a general pardon issued by the government in the city of Tobruk backed by renegade General Khalifa Haftar, one of two rival administrations based in Libya.

The second of Muammar Gaddafi's nine children, Saif al-Islam had been seen by many before the 2011 uprising as his father's heir apparent and the second-most powerful man in Libya.

Saif al-Islam remained prominent throughout the violence that gripped Libya in the wake of the Arab Spring. There were numerous allegations against him of torture and extreme violence against opponents of his father's rule. By February 2011, he was on a United Nations sanctions list and was banned from travelling.

In June 2011, he announced that his father was willing to hold elections and to step down if he did not win them. However, NATO rejected the offer and the bombardment of Libya continued.

By the end of June 2011, the International Criminal Court (ICC) issued an arrest warrant against him, but he remained at large until after the death of his father Muammar and his brother Mutassim in Sirte, on October 20, 2011.

Following long negotiations with the ICC, which had been calling for his extradition, Libyan officials were granted authority to try Saif al-Islam in Libya for war crimes committed during the 2011 uprising.

At the time, Saif al-Islam's defence lawyers feared that a trial in Libya would not be motivated by justice, but would be motivated by a desire for revenge. The UN had estimated that up to 15,000 people were killed in the conflict, while Libya's National Transitional Council placed the figure as high as 30,000.

In 2014, Saif al-Islam appeared via video link in the Tripoli courtroom where his trial was held, as he was incarcerated in Zintan at the time. In July 2015, the Tripoli court sentenced him to death in absentia.

READ MORE: Libya - The story of conflict explained

A Western-educated and well-spoken man, Saif al-Islam presented a progressive face to the oppressive Libyan regime and was extremely visible and active in the drive to repair Libya's relations with the West between the year 2000 and the start of the 2011 uprising.

He received a PhD from the London School of Economics (LSE) in 2008. His dissertation dealt with the role of civil society in reforming global governance and was prominent in his calls for political reform.

LSE was later condemned for having sought a relationship with the Libyan regime, namely for accepting Saif al-Islam as a student, who had signed an agreement for a $2.4m gift from the Gaddafi International Charity and Development Foundation on the day of his doctorate ceremony.

As an internationally prominent negotiator and influencer, Saif al-Islam could claim a number of victories and prominent roles. He played a pivotal role in the nuclear negotiations with Western powers including the United States and the UK.

Also in negotiating compensation for families of victims of the Lockerbie bombing, the Berlin nightclub attack, and the UTA Flight 772, which detonated over the Sahara desert.

WATCH: Saif al-Islam Gaddafi interview (22:15)

He also mediated the release of six medics - five of whom were Bulgarian - who were accused of infecting children with HIV in Libya in the late 1990s. The medics were imprisoned for eight years in 1999 and, upon their release, announced that they had been tortured while in detention.

He had a number of other proposals including "Isratine", a proposal for a permanent resolution of the Palestinian-Israeli conflict through a secular one-state solution. He also hosted peace talks between the Philippines government and leaders of the Moro Islamic Liberation Front, which resulted in a peace agreement that was signed in 2001.

Saif al-Islam is still wanted by the ICC on charges of war crimes and crimes against humanity. 

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