"The Libyan government received today Saadi Gadhafi and he arrived in Tripoli," the cabinet of Prime Minister Ali Zeidan said in a statement on Thursday.
Libya's interim government had been seeking the extradition of Saadi, who took refuge in the country's southern neighbor Niger after the 2011 NATO-backed uprising that toppled his father.
Libyan authorities thanked the Niger government for its cooperation in handing over Saadi and promised he would be treated "in accordance with international law."
A government-backed militia website showed what it said were photos of Saadi wearing a blue prison uniform, while Libyan news websites ran pictures showing him with his head shaved in prison.
Saadi, who is the former commander of Libya's special forces and an ex-footballer, is one Gadhafi's seven sons. He is not wanted by the International Criminal Court (ICC), however, unlike his brother Seif al-Islam. But Libya wants to try him for allegedly misappropriating property by force and alleged armed intimidation while he was head of the country's football federation.
dr/hc (Reuters, dpa, AP)