MAIDUGURI/KADUNA, Nigeria: Nigerian Islamist sect Boko Haram said on Monday it killed 12 soldiers in an attack in the northeast town of Maiduguri but security forces denied any of its officers had been killed and said it shot dead sect members.

Boko Haram, which wants Islamic law more widely applied, has killed more than 250 people this year in bomb and gun attacks on cities across the north of Africa's most populous nation.

President Goodluck Jonathan, a Christian southerner, has been criticised for not getting to grips with the sect, whose attacks have become increasingly sophisticated and deadly.

Nigeria's population of over 160 million people is split roughly equally between a Muslim north and a Christian south.

Although the majority of the strikes are in the sect's home region in the far northeast, where Nigeria borders Chad, Cameroon and Niger, the group is increasingly striking in other northern cities.

Security experts and Jonathan have said Boko Haram has ties with jihadist groups outside Nigeria, including al Qaeda's north African wing. Problems of poverty, which is more severe in the north than the south, and government corruption feed the unrest.

"Yesterday (Sunday) we carried out an attack on military formations at Baga town on the shores of Lake Chad as well as on the JTF in the selected areas of Maiduguri where we killed 12 soldiers and many civilians," Abu Qaqa, Boko Haram spokesman, told reporters by phone in Maiduguri.

The joint task force (JTF) in charge of tackling the unrest in the northeast, where Boko Haram first emerged in 2003, dismissed the allegation and said it had achieved a victory.

"Yesterday soldiers of the JTF were attacked in Budum ward of Maiduguri by Boko Haram sect members. In the exchange of fire following the attack 12 sect members were killed while two members of the JTF sustained injuries."

ARRESTS

Nigeria's state security service (SSS) last week recaptured the main suspect in a deadly Christmas Day bomb attack outside the capital Abuja which killed 37 people. He had escaped from police custody in January in suspicious circumstances, prompting Jonathan to sack the chief of police and his deputies.

The SSS also said they arrested Abu Qaqa on Feb. 1 but the sect said the security forces had captured a different senior member of the sect called Abu Darda. Reporters in Maiduguri have said Abu Qaqa is still speaking on behalf of the sect, while the SSS have declined to comment again on who is in custody.

"I wish to state that arresting our leaders will not deter us in anyway but rather it emboldens us to be more vicious in our operations," Qaqa said on Monday.

In the northern city of Kaduna, security forces wounded the director of finance for the state government after he forced his car into Government House.

Reuben Buhari, spokesman for the governor, said earlier on Monday that the car was loaded with explosives and the government worker was shot because he was suspected of being a suicide bomber. The police said investigations were ongoing but made no mention of a bomb.

"The driver drove dangerously in a suspicious manner towards the Government House gate. The security personnel stopped the lone occupant, but instead of stopping, he forced himself through the exit gate and found his way into the Government House," Ballah Magaji Nasarrawa, Kaduna police commissioner, said in a statement.

"The security agencies thereafter, opened fire and shot the suspect on the leg and lower abdominal part of his body."

Jonathan has said Boko Haram has infiltrated parts of government and security forces.

Boko Haram's attacks in northern Nigeria have rapidly overtaken sabotage strikes on oil pipelines and kidnappings by militants hundreds of kilometres away in the southern Niger Delta as the country's biggest security threat.

Although an amnesty in 2009 significantly reduced violence in the southern oil region, there is still regular unrest.

Pirates shot dead the captain and the chief engineer on a cargo ship off the coast of Nigeria on Monday, an International Maritime Bureau (IMB) official said, the latest in a string of attacks on vessels off the coast of Africa's No. 1 oil producer.