Authorities in Nigeria say suspected members of a radical Islamist group have attacked a police station and two banks in the country's northeast, killing at least 12 people.

Officials say the attackers stormed into the town of Gombi Thursday, first bombing the police station and then raiding branches of First Bank and Union Bank.

Police say at least four police officers, one solider and seven bank workers were killed in the attacks.

They say the gunmen left the banks with an unknown amount of cash.

Police blame the killing on the Boko Haram group, which has carried out a series of attacks, mostly in northeastern Nigeria. The group is believed to be responsible for attacks on police, politicians, community leaders and religious figures.

Boko Haram has called for sharia, or Islamic law, to be applied more widely and strictly across Nigeria.

It launched a violent uprising in July 2009 that was crushed by the Nigerian military. Since then, the group has targeted authority figures in shootings and carried out numerous bombings.