BAMA, Nigeria -- The latest attack by suspected Islamic extremists in Nigeria's northeast has left 115 people dead, more than 1,500 buildings razed and some 400 vehicles destroyed, witnesses said Thursday, as a traditional ruler accused the military of being scared to confront the militants.

Sitting amid the smoking ruins of his palace, the shehu, or king, of Bama, Kyari Ibn Elkanemi, charged that the government "is not serious" about halting the Islamic uprising in a region covering one-sixth of the country, far from oil fields that make Nigeria Africa's biggest petroleum producer.

Wednesday night's attack on Bama town, an agricultural and commercial centre, came the day the leader of the Boko Haram terrorist network warned leading Nigerian Muslim politicians and religious and traditional leaders that his fighters will target them for pursuing democracy and Western-style education.

In the video message, punctuated by the crackle of automatic gunfire, Abubakar Shekau said: "The reason I will kill you is that you are infidels, you follow democracy. ... Whoever follows democracy is an infidel and my enemy." Shekau spoke in the local Hausa and Kanuri languages in the video, obtained by the AP Thursday through channels that have provided previous communications.

Many more Muslims than Christians have been among the thousands of people killed in the 4-year-old rebellion by his Boko Haram -- the nickname means "Western education is forbidden -- which aims to transform Nigeria into an Islamic state, even though half the more than 160 million citizens are Christians.

The shehu's attack on the government and the military came the week Nigeria's Defence Ministry has been defending itself after the governor of the state most affected by the uprising, Kashim Shettima of Borno, told President Goodluck Jonathan that Boko Haram are "better armed and better motivated" than security forces.

According to Shehu Ibn Elkanemi, "Boko Haram has established recognized camps which are known to many of our people but the security are afraid to approach them. Each time the civilian JTF (vigilante force) wants to go, the security will not allow them."

Brig. Gen. Chris Olukolade, the Defence Ministry spokesman, said in a statement this week that recent attacks are being perpetrated by extremists who are fleeing the military's aerial bombardment and follow-up ground assaults on forest hideouts.

Olukolade said they have the militants on the run.

Attacks like the one on Bama would appear to contradict that.

Gov. Shettima said the attacks are becoming more frequent and deadly. At least 150 people were killed in weekend attacks on eight Borno villages; at least 11 killed in another village attack on Monday; one soldier and an unknown number of civilians killed when militants attacked the home of a retired general on Tuesday; 39 killed and more than 1,000 homes burned down on Feb. 11. The figures are conservative as victims often die in the hospital without any report being made.

Jonathan appeared to respond almost immediately to the Borno governor's request for more resources as an AP reporter watched a convoy of trucks transporting tanks and other armoured vehicles and heavy weaponry into the war zone on Wednesday.

One truck overturned on a narrow bridge in Adamawa state, plunging into a river and injuring several soldiers.

In Bama on Thursday, the chief nursing officer at the general hospital, Muhammadu Shuwa, told The Associated Press that they admitted 200 patients wounded in the attack and 17 died of injuries.

Akura Satoma, leader of youth vigilantes in Bama, said they recovered and buried 98 bodies -- some shot, some beheaded, others killed in fires that the militants set with homemade bombs.

Satoma said his group and the military killed many extremists, but that he could not give a figure because the militants quickly collect their dead. He appeared in awe of the militants' tactics.

"The way they operate is so amazing because as soon as their member is killed, they pick the corpse," he said. "They seemed to have specific people for designated duties: while some were shooting RPGs (rocket-propelled grenades), others are planting bombs, others are breaking shops and houses and looting food items and other consumables which they haul into waiting trucks. Some others, like the teenagers, were seen helping to deliver ammunition while others were helping in picking corpses."

Associated Press reporters Michelle Faul in Lagos, Nigeria and Ibrahim Abdulaziz in Yola, Nigeria, contributed to this report.