Attackers on Friday opened fire and threw explosives at government buildings in a north-eastern Nigerian town along the border with Cameroon that has hit previously by robbery gangs, police and residents said.
It was unclear if there were casualties from the attacks in Maiha. Some residents said they suspected Islamist extremist group Boko Haram, but criminal gangs have also repeatedly carried out violence around border posts in the area.
"We received information on the attacks in Maiha," said Adamawa state police spokesperson Mohammed Ibrahim.
"We are on our way to Maiha to assess the situation and until we get there I can't give details on damage and casualty recorded."
Residents said a group of about 40 gunmen arrived in the town around 01:00 in all-terrain vehicles, on motorcycles and on foot chanting "Allahu Akbar".
They then opened fire and threw explosives at a police station, a prison, a courthouse, an education administrative building and a government lodge, leaving them badly damaged, according to residents.
Violence linked to Boko Haram's insurgency in northern and central Nigeria is believed to have left some 3 000 people dead since 2009, including killings by the security forces.
However, some Nigerian border areas are also notorious for violence linked to criminal activity, and gangs have also carried out attacks under the guise of Boko Haram.