Security personnel were killed by bandits in Zamfara State when they attacked a military base.
The attackers set fire to houses and stole weapons, according to security sources cited by AFP.
The exact perpetrators of the Mutumji raid were not immediately known, but the army is engaged in operations in Zamfara against armed criminal gangs known as bandits who are responsible for a series of mass abductions.
In an attempt to disrupt bandit communication during the crackdown, telecommunication services have also been cut in Zamfara and in parts of neighbouring State Katsina.
According to one security source, the attackers stormed the base around 10:30 am and engaged the troops in a gun battle.
Twelve soldiers were killed when the troops were subdued. Nine navy members, a soldier, and two police officers were among them.”
The casualties were confirmed by a second security source.
Mutumji, Dansadau district, about 80 kilometers (50 miles) from the state capital Gusau, is a key site for logistics and reconnaissance in the army’s fight against bandits in the area.
In Borno State, the epicenter of a 12-year insurgency that has killed 40,000 people, gunmen often attack military bases.
Large, heavily armed criminal gangs that raid villages and kidnap for ransom in the Northwest and Central States have also become more brazen.
Bandit gunmen shot down an air force jet over Zamfara in July while it was returning from operations.
The pilot ejected safely and escaped capture.
The gunmen also attacked the country’s elite defence academy in northwest Kaduna State last month, killing two officers and kidnapping another.