Mauritanian authorities arrested former Libyan leader Muammar Gaddafi's chief of intelligence, Abdullah Al-Senussi, as he arrived at Nouakchott airport, Mauritania's official state news agency AMI said on Saturday.

It said Senussi, who has been indicted by the International Criminal Court on charges of crimes against humanity, arrived late on Friday from Casablanca in Morocco, bearing a falsified Malian passport.

The Hague-based ICC issued an arrest warrant in June 2011 for both Senussi and Gaddafi's son Saif al-Islam, who was captured disguised as a Bedouin in the Sahara desert in November.

Both men have been charged as being "indirect co-perpetrators" of murder and persecution.

Mauritania has not signed the Rome Statute governing the ICC and authorities were not immediately available to comment on what they planned to do with Senussi.

Senussi is suspected of a key role in the killing of more than 1,200 inmates at Tripoli's Abu Salim prison in 1996. It was the arrest of a lawyer for victims' relatives that sparked Libya's Arab Spring revolt in February last year. – Reuters