ONITSHA, Nigeria -- Bank robbers armed with assault rifles and explosives attacked four banks and two police stations in southern Nigeria, in a coordinated strike that left seven people dead, police said Tuesday.

It was the latest in a spate of security lapses in Nigeria in the recent days, after a suicide bombing by suspected Islamists inside a military barracks Sunday and a jail break in the capital Abuja early Monday.

The attack took place late Monday night in the remote town of Auchi, in Edo state. The robbers opened fire and detonated dynamite at several of the targets, police commissioner for Eddo state Hurti Mohammed told Reuters by telephone.

They robbed the vault in Access Bank but were unable to get money out of any of the other banks. Seven people, including a bus driver, were killed in the ensuing gunbattle with police, he said.

'They shot sporadically'
Mohammed added that the robbers had escaped.

"They shot sporadically and were able to gain access to the vault of one of the banks ... carting away an unspecified amount of cash," he said. 

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The southern, Yoruba-dominated area where the attack took place was hundreds of miles away from the northern areas where Islamist insurgent group Boko Haram is violently challenging the authority of the President Goodluck Jonathan's government.

But Boko Haram have made forays into the south, including in Kogi state, which borders Edo to the north.

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Mohammed rejected any link. Powerful, organized robbery and kidnapping rings operate across southern Nigeria.

"There is no relation between this incident and what is happening in the north," he said. "We suspect the attackers just to be robbers."

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