Nigeria's military has declared a 24-hour curfew on a dozen neighborhoods in a northeastern city that is a stronghold of the armed group Boko Haram.

The military deployed jets and helicopters to carry out air strikes on fighter camps, and said 10 fighters had been killed and another 65 arrested.

A spokesman for Defense Headquarters also said the military had seized stockpiles of weapons including rocket-propelled grenades, guns and ammunition from areas around Maiduguri, the main city in the northeast.

Boko Haram, which has said it is fighting to create an Islamic state in Nigeria's mainly Muslim north, has carried out scores of attacks in recent years, and has become emboldened and better armed in recent months.

Nigeria launched a massive offensive against the group this week, deploying several thousand troops across three states where President Goodluck Jonathan declared a state of emergency after the fighters seized territory and chased out the government.