A Boko Haram suicide bomber has killed 9 people and injured dozens at a mosque in the Nigerian city of Maiduguri.

The attack comes after an overnight assault on the city by the Islamic militants. 13 people were killed during sustained RPG fire before troops repelled the assault.

The attacks come only one day after Muhammadu Buhari was sworn in as Nigeria's new president.

Buhari has vowed decisive action against Boko Haram. According to the BBC, he called Boko Haram a "godless group, who are as far away from Islam as one can think."