MAIDUGURI, Nigeria — Nigeria's army says security forces have killed seven suspected radical Islamist sect members in a besieged northeast Nigerian city.

Spokesman Lt. Col. Sagir Musa said in a statement Friday that a clash involving a special unit of army and police occurred Thursday in Maiduguri.

Musa said suspected Boko Haram gunmen started shooting at officers as they searched for sect hideouts in a busy residential area. The statement did not say if officers were hurt.

The clash came hours after coordinated attacks on mobile phone towers caused partial network failure in Maiduguri and other parts of northern Nigeria.

There was no claim of responsibility for the tower attacks Friday, but Boko Haram has threatened phone companies in the past.