Gaddafi Son Under House Arrest in Niger.

Authorities in Niger have put Al-Saadi Gaddafi, the son of slain Libyan leader Muammar Gaddafi, under house arrest after he said in a television interview that an uprising was imminent in his homeland, a Libyan official says.

"The move followed contacts between the two countries," Mohammed al-Hareezi, the spokesman for Libya's ruling National Transitional Council (NTC) told the broadcaster Al-Arabiya.

The NTC said on Saturday that Niger had to hand over the younger Gaddafi and other fugitives "at the earliest possible time to preserve its relations and interests with the Libyan people".

Al-Saadi Gaddafi, who took refuge in Niger in September, told Al-Arabiya on Friday in a telephone interview that an "uprising is growing every day" in Libya.

"I have contacts almost on a daily basis with many Libyan groups," he said.

"Many of them are still working with us," the businessman and former footballer, added.

Al-Arabiya, citing a Libyan government source, reported late on Saturday that Niger had detained Al-Saadi, seized his mobile phone and kept him in an unknown location.

Niger said in September it would not extradite him to Libya over fears that he would be killed.