The Nigerian army says it has arrested a commander of Boko Haram.
Shuaibu Muhammed Bama was detained at the home of a senator in the city of Maiduguri earlier this week. The senator, who was not named, denies the claim.
Boko Haram is fighting to overthrow the government and impose Sharia law across Nigeria.
A BBC correspondent says the army's claim that the suspect was in a senator's house has fuelled a debate on whether politicians are helping the group.
Another senator was arrested last year and charged over links to Boko Haram. The senator denied any wrongdoing and was later released on bail.