KANO, Nigeria: Around 30 gunmen rained bombs and gunfire on a police station in Kano, killing a woman in the latest attack blamed on Islamist group Boko Haram in Nigeria's second city, residents said.

The northern city has lived in fear amid continued chaos since a coordinated wave of attacks after Muslim prayers on Friday killed at least 185 people, Boko Haram's deadliest ever onslaught.

The converged on the station from two different directions on motorcycles and in a Mercedes car late Tuesday, witnesses said.

The gunmen "were just telling people to move away, they were just here to do their work. They just opened fire on the police station," a resident who requested anonymity told AFP on Wednesday.

The station, in Kano's densely populated Sheka area, was heavily damaged in the attack: its windows were shattered, the walls were smoke-stained and blood had covered nearly the entire bathroom floor, according to AFP reporters.

The holding cells at the back of the station had been opened.

A purported spokesman for Boko Haram has said last week's attacks were in response to a refusal by the authorities to release arrested members of the group from custody.

A huge crowd had gathered outside the station on Wednesday, surveying the wreckage after the assault that also injured at least one policeman, according to witnesses.

No police were in sight, just neighbourhood youths trying to control the crowd.

"A policeman was shot in the leg. A woman who came to see a policeman was shot in the stomach. She died," the same resident told AFP, adding that the woman was standing outside the station's gate and talking to the officer when she was shot.

Residents said the attackers hurled two bombs at the station before opening fire.

"It was around 6:30 pm (1730 GMT) when people were preparing for the evening prayers and a large group of gunmen arrived in the area and opened fire on the police station and threw in bombs," one witness said.

Kano, an ancient Muslim city of 4.5 million, had hitherto escaped the increasingly sophisticated attacks blamed on Boko Haram, a group that has said it wants to create an Islamic state in northern Nigeria, and which some believe has Al-Qaeda ties.

Mali's Foreign Minister Boubeye Maiga said Tuesday there was a "confirmed link" between Boko Haram and Al-Qaeda's North Africa franchise, at a security meeting of Sahel states in Mauritania also attended by Nigeria.

At checkpoints set up across Kano on Wednesday security forces were stopping vehicles and ordering drivers to open their car's boot for inspection.

The army was manning the checkpoints in the Christian neighbourhood of Sabon Gari, while the local police were in charge elsewhere, AFP correspondents said.

Security forces have also imposed a strict sundown curfew across the city.

All of Kano's banks have been closed since Friday and some residents complained that their businesses will collapse if they cannot access cash soon.     A group of 30 people had crowded around one bank, where an ATM was still dispensing money, according to AFP reporters.

Earlier on Tuesday, gunfire erupted when security forces raided a house suspected to be a Boko Haram hideout shortly after midnight.

They opened fire and a suspect fired back, resulting in a shootout lasting around four-and-half hours and sending residents into panic.

According to Human Rights Watch, Boko Haram has killed more than 935 people since the group -- whose name can be loosely translated as "Western education is sin" -- launched a violent campaign in July 2009.

More than 250 of those deaths have come in 2012 alone.

President Goodluck Jonathan has vowed to beef up security as he grapples with the worst crises of his nine-month tenure -- a surge in Boko Haram attacks and mounting social discontent.

Military spokesman Colonel Mohammed Yerima said Wednesday that troops had withdrawn from the streets of the commercial capital Lagos following a public outcry over their deployment in the wake of mass fuel protests.

Jonathan set off the protests when he abolished fuel subsidies on January 1, causing petrol prices to more than double.