Nigeria's military killed 13 members of the Islamist militant group Boko Haram and lost one soldier on Tuesday in a gun battle in Maiduguri, the group's northeastern stronghold, the army said.
Boko Haram, which is loosely based on the Afghan Taliban, killed hundreds last year in a campaign to impose shariah, or Islamic law, in Nigeria, a country of more than 160 million split roughly equally between Christians and Muslims.
At least 32 people have now died in the northeast in the last week alone in violence presumed to be linked to Islamist militancy, the biggest threat to stability in Africa's main oil exporter.
"One soldier was killed by Boko Haram while the JTF killed 13 Boko Haram," Sagir Musa, spokesman for the military Joint Task Force, said on Tuesday.
The military in the northeast have in the past played down their own casualties in fighting with Boko Haram.
Musa said members of the sect had detonated a bomb at a JTF checkpoints in Maiduguri, and that all the deaths had occurred in the ensuing gun battle.
Maiduguri, a remote dusty town close to the borders of Chad and Niger, has been a hotbed of violence, directed mostly at the security forces, since Boko Haram took up arms in 2009.
Boko Haram's insurgency intensified after Goodluck Jonathan, a southern Christian, was elected president in April 2011.
Jonathan has been unable to stop the rebellion despite waves of military offensives in the northeast and other parts of northern and central Nigeria where Boko Haram has a strong presence.
Western governments are increasingly concerned about Islamists in northern Nigeria linking up with outside groups, including al Qaeda's north African wing.
The Islamist group Ansaru, known to have ties with Boko Haram, appears to have become more active in recent weeks. It claimed an attack on a major police barracks in the capital Abuja last month, where it said hundreds of prisoners had been released.
The group, which has been labeled a "terrorist group" by Britain, has also said it was behind the kidnapping of a French national last week.
Reporting by Ibrahim Mshelizza; Writing by Joe Brock; Editing by Kevin Liffey
© 2012 Thomson Reuters. All rights reserved.