Tim Cocks / Reuters, file
Nigerian forces gather Monday in the Islamist stronghold of Maiduguri. Soldiers poured in this weeek before the military on Friday launched a major offensive against the insurgents.
MAIDUGURI, Nigeria -- Nigerian forces used jets and attack helicopters to bombard Islamist militant camps in the northeast on Friday, in their biggest military offensive since Boko Haram launched an uprising in 2009.
"A number of insurgents have been killed," the defense headquarters spokesman said, including at the Sambisa game reserve in Borno state, the epicenter of the insurgency.
"It is not just Sambisa. Every camp is under attack. But we have not done the mopping-up operations on the ground to determine the numbers killed," Brig. Gen. Chris Olukolade said by telephone. Another military source, who declined to be named, said at least 30 insurgents had been killed.
Nigerian forces are trying to regain territory controlled by increasingly well-armed Boko Haram Islamist insurgents in their northeastern stronghold states of Borno, Yobe and Adamawa, put under a state of emergency by President Goodluck Jonathan on Wednesday.
More troops arrived in the Borno state capital, Maiduguri, on Friday, witnesses said.
"I saw more than 20 trucks loaded with soldiers fully kitted for battle towards Marte. I wish them luck in ending this BH (Boko Haram) madness," resident Ahmed Ibrahim said by telephone.
Beyond the region covered by the state of emergency, gunmen stormed a police station and a bank, the army said, a sign the offensive could provoke violence by smaller militant cells across the north.
Boko Haram, other Islamist militant groups such as al-Qaeda-linked Ansaru and associated criminal gangs have become the biggest threat to stability in Africa's top oil-producing nation.
Thousands have been killed since Boko Haram launched an uprising almost four years ago in an effort to create an Islamic state in a country of about 170 million split roughly equally between Christians, who are the majority in the south, and Muslims, who predominate in the north.
Violence has mostly happened far from the commercial hub, Lagos, or political capital, Abuja, and hundreds of miles away from oilfields in the southeast.
Military jets, helicopter gunships and thousands of troops are involved in the current offensive, which may answer some critics who accuse Jonathan, a southern Christian, of underestimating the severity of the crisis in the Muslim north.
Rights groups are concerned the state of emergency will lead to more abuses they have document by Nigerian forces.