The Nigerian army says it has repelled an assault by Boko Haram Islamist militants on the strategic north-eastern city of Maiduguri.
Defence Ministry spokesman Chris Olukolade is quoted as saying the attack was "contained" and the rebels suffered heavy casualties.
The militants attacked in the early hours of Sunday, and gunfire was reported on the streets of the city.
Last week's assault by Boko Haram on the city was also stopped by the army.
Boko Haram began guerrilla operations in 2009 to create an Islamic state. It has taken control of many towns and villages in north-eastern Nigeria in the last year.
The conflict has displaced at least 1.5 million people, while more than 2,000 were killed last year.'Stray bullets'
Brig Gen Olukolade was quoted by the AFP news agency as saying that "the terrorists incurred massive casualties" on Sunday.
"The situation is calm as the mopping up operation in the affected area is ongoing," he added.
A number of eyewitnesses confirmed the army claim.
They also said that several civilians had been hit by stray bullets and bombs during the fighting.
The army was supported by vigilantes who recently have taken a central role in fighting the militants.
The military's handling of the six-year insurgency has often been criticised.