BBC News:
Some 480 Nigerian soldiers have crossed into Cameroon following fierce fighting with Boko Haram militants.
Reports claimed that the troops had joined thousands of citizens fleeing the fighting, but Nigeria said they were conducting a “tactical manoeuvre”.
Clashes are said to be continuing in the border town of Gamboru Ngala.
Boko Haram on Sunday released a video claiming that it had established an Islamic state in the towns and villages it controls in north-eastern Nigeria.
The group’s five-year insurgency has intensified in recent months despite the deployment of thousands of extra troops to the worst-affected areas.
