Explosions and gunfire have hit the northern Nigerian city of Damaturu in a suspected attack by the militant Islamist group Boko Haram, according to residents.
The sound of blasts and heavy weapons was reported by locals in the Gujba Road area of Yobe's state capital in the early hours of the morning.
"We have left our homes. We are now in the bush. We don't know what's going to happen," local citizen Umar Sada told AFP news agency.
Sada added that a police barracks had been destroyed in the attack.
Another resident, cameraman Mustapha Usman, told Reuters that a Nigerian military jet was seen flying over the city following the offensive.
"I saw a military jet circling three times. People have abandoned their vehicles on the road and gone home," Usman said.
The number of casualties caused by the offensive remains unknown.
Last week, three bomb blasts struck a mosque in northern Nigeria's largest city, Kano, during Friday prayers.