Nigerian troops on Saturday killed 11 fighters from the Islamist sect Boko Haram during a shootout in the northeastern city of Maiduguri, a spokesman said.

"Today, in an exchange of fire during a cordon-and-search operation conducted by the JTF, 11 Boko Haram members were killed," Lieutenant Colonel Hassan Mohammed told AFP by telephone, referring to the army's Joint Task Force unit.

Mohammed said no casualties were suffered by the JTF, a specialised squad set up last year to crack down on Boko Haram, a shadowy group that is blamed for the deaths of more than 200 people already this year.

Maiduguri, the capital of Borno state, was placed under a state of emergency on December 31 by President Goodluck Jonathan along with other parts of the country hard hit by Boko Haram's attacks.

The city is seen as Boko Haram's base.