Witnesses in Nigeria say gunmen attacked a police station in the northern part of the country late Monday, killing several police officers.
The gunmen, suspected members of the radical Boko Haram Islamic group, also attacked a nearby bank in the town of Kankara in the far northern state of Katsina.
Several days ago, Boko Haram claimed responsibility for a suicide bombing outside Nigeria's national police headquarters in Abuja, killing at least one other person.