Baghdadi al-Mahmoudi, who was extradited on Sunday from Tunisia to Libya, was loyal to Muammar Qaddafi until the end, serving as premier from 2006 up to the final days of his regime.
A physician by training, Mahmoudi arrived in a private plane to Tripoli, where he was immediately transferred to prison under orders of the Libyan prosecutor general.
“(Mahmoudi is) charged of committing crimes against the Libyan people,” Libyan interim Prime Minister Abdel Rahim al-Kib told journalists.
His extradition represents a major diplomatic victory for Libya's interim government which has been keen to prove to the world that it can conduct fair trials for ex-regime figures.
Mahmoudi is also the first senior official to be sent back for trial in Libya and his extradition could set a precedent for other countries who have sheltered members of Qaddafi’s regime.
Libya wants to try Mahmoudi, who is said to have been born in 1945 in the coastal town of Zawiyah, for inciting rape during last year's conflict, according to his defense team.
Mahmoudi fled to neighboring Tunisia last September shortly after rebel fighters seized the capital Tripoli, effectively putting an end to more than four decades of iron-fisted rule.
He was arrested on September 21 on Tunisia's southwestern border with Algeria and jailed for illegal entry.
Mahmoudi had appealed his extradition request on the grounds that he had applied for refugee status and could face execution if sent back to Libya, where the new authorities are still struggling to impose the rule of law.
In May, Mahmoudi staged a hunger strike in protest over the extradition deal brokered between Tunisia and Libya, fearing for his life as the sole holder of Libyan state secrets since Qaddafi’s death on October 20.
From March 5, 2006 through the war of 2011, Mahmoudi was the Secretary of the General People's Committee, the equivalent of the country's prime minister.
He held a series of government posts before that, including health minister from 1992 to 1997, as well as shorter stints as minister of human resources and minister of infrastructure.
Mahmoudi oversaw vast fortunes in the oil-rich nation as chairman of the Libya Investment Authority, one of the largest sovereign wealth funds in the world which was created in 2007 to restructure state enterprises.
He also oversaw the Libyan Oil and Gas Counil which was created in 2006.
Mahmoudi sparked a major frenzy in French media this year with claims that Qaddafi had funded Nicolas Sarkozy's 2007 presidential campaign to the tune of 50 million euros ($65 million).
Lawyer Slim ben Othman told AFP that his client claimed to have personally handed the money to Sarkozy representatives in Geneva and that the issue had been discussed during an October 25 hearing in Tunis.
Former French President Sarkozy rejected the claims in May as “grotesque.”
Mahmoudi faces an uncertain fate in his home country which is gearing up for July 7 elections for a general national congress, the first national poll since Qaddafi’s ouster.
Rights groups have repeatedly stressed the need for judicial reform in Libya which was left with a weak state and powerful militias lording over justice and jails with impunity.