A military strike on a Boko Haram camp in Nigeria's northeast region last week killed 150 of the outlawed group's fighters and 16 soldiers, an army spokesman has said.

The army's offensive against the armed group came on September 12, after local media reported that Boko Haram had ambushed a group of soldiers in the same area, killing 40 and leaving dozens of others missing.

Military officials were not available to comment on the reported Boko Haram ambush, speaking only about the purported military strike.

"It was a highly fortified insurgent camp with heavy weapons in [northeastern] Borno State," army spokesman Ibrahim Attahiru said on Wednesday, adding that the camp was in the Kasiya forest.

"The army raided the camp on September 12. Some 150 Boko Haram terrorists were killed, while the military lost 16 soldiers. Nine soldiers are still missing," he said.

Military shutdown

Borno was placed under a state of emergency in mid-May. The military shut down the mobile phone network in the region to block the armed group from coordinating attacks.

With the communication network switched off, details of attacks have been slow to emerge and difficult to verify. Residents have been largely unreachable, with military statements forming the main source of information in the ongoing offensive against Boko Haram.