Boko Haram insurgents overran most of a north-eastern Nigerian town on Tuesday after hours of fighting that killed scores and displaced thousands of residents, security sources said.
The Islamists launched an attack on the town of Bama, 70km from the Borno state capital of Maiduguri, on Monday.
They were initially repelled but came back in greater numbers overnight, the sources and witnesses said.
Nigerian defence spokesman did not respond to a request for comment.
The sources said there were heavy casualties on both sides and one said at least 5,000 people fled the town.
In a bungled air strike, several Nigerian troops were killed at the Bama armoury by a war plane targeting the insurgents, a soldier on the ground said.
Two months after Islamist militants in Iraq and Syria declared the area they seized as an Islamic ‘caliphate’, Boko Haram has also for the first time explicitly laid claim to territory it says it controls in parts of northeast Nigeria.
They captured the remote hilly farming town of Gwoza, along the Cameroon border, during fighting last month. The group’s leader Abubakar Shekau in a video declared it a “Muslim territory” that would be ruled by Islamic law.