Heavy explosions and gunfire rocked the northeast Nigerian town of Potiskum early Wednesday, residents said, after violence this week left at least 24 people dead in the city of Maiduguri.

Blasts and shootings shook residents of Potiskum, previously hit hard by violence blamed on Islamist extremist group Boko Haram, but it was not clear whether they were due to a military raid or some type of attack, residents said.

"It all started at 5:50 this morning, shortly after the morning prayers," one resident told AFP. "It started with a huge explosion followed by successive blasts and gunfire. I can still hear explosions and shootings." Another resident said the explosions and shootings "have been going on for the past 40 minutes".

The blasts and gunfire were coming from an area of the town where a bank, a military base and the office of the anti-narcotics agency are located, residents said. Police and military officials were not available for comment. Potiskum, the commercial hub of Yobe state, has been hard hit by Boko Haram attacks in recent months.

On Tuesday, Nigeria's military said 24 Boko Haram members were killed in violence that rocked the city of Maiduguri after the extremists launched attacks with bombs and rocket-propelled grenades.

The military has been regularly accused of abuses, including the killing of civilians. The statement said there were no civilian casualties and one soldier was wounded, but the claims could not be independently verified. Maiduguri is considered the base of Boko Haram. The conflict is believed to have killed at least 2,800 people since 2009.