Saif al-Islam, former Libyan leader Muammar Gaddafi's son, was spotted on Wednesday morning in north Arlit (about 400 km north of Agadez) in the Nigerien territory.

A military brigade had been sent to look for him, military sources said.

Saif al-Islam was being escorted by pro-Gaddafi fighters and had already established contacts with the Nigerien Armed Forces (FAN) in the Agadez region.

A Nigerien military source said on Monday night that Saif al-Islam had tried to cross over to the Nigerien territory in the extreme northern parts of the country, on the border with Libya.

Saif al-Islam and his brother-in-law Abdallah al-Senoussi are being sought by the International Criminal Court (ICC) for committing crimes against humanity.

A governmental source from Niamey said al-Senoussi who was serving as Gaddafi's head of intelligence was spotted last week in the extreme northern parts of Niger.

Since September, Niamey has been hosting close confidants of Gaddafi including his son Saadi Gaddafi "for humanitarian reasons."