A suicide bomber driving a three-wheeled vehicle detonated near the office of the Directorate of State Security Services in Nigeria’s northeastern city of Maiduguri on Saturday.

Security sources said the blast went off a few metres from the office at about 7 a.m. local time (0600 GMT). One of the security sources said one person was killed, as well as the bomber, while a hospital source said four people were being treated for injuries.

The city, the birthplace of Islamist militant group Boko Haram, is frequently hit by bombings.

It has been the target of several attacks since Muhammadu Buhari, made it the command centre for the campaign against the militant group after being inaugurated on May 29.

Two suicide bombers blew themselves up near a Maiduguri hospital during a visit by the vice president at the start of July and, a few days later, Boko Haram militants attacked the city from the outskirts.