"The extremists were hit inside their camps since Wednesday in the affected states," Army spokesman Brigadier General Chris Olukolade said yesterday.
The spokesman said a military plane was hit by an anti- aircraft missile used by the insurgents during the airstrikes yesterday but it was able to be piloted back to the base.
Olukolade did not give the exact number of militants killed in the air raids but said "dozens of the insurgents have been killed."
A large number of troops have been deployed to the oil-rich country's border posts to prevent the fundamentalists from escaping.
Also Read
He had warned that the military will take "all necessary action" to "put an end to the impunity of insurgents and terrorists."
The air strike is under way in all three states put under emergency decree, but the extremists' traditional base of Borno state is expected to see the most intense fighting.
Meanwhile, mobile telephone services suddenly went off in the affected states, a few hours after the declaration of state of emergency.
The group, which says it abhors western education, has vowed to replace Nigerian government with an Islamic rule.