Hundreds of residents have fled the towns of Bama and Gwoza in Borno State following attacks and threats by suspected members of the Islamist militant sect Boko Haram

The insurgents were moving from house to house, issuing threatening letters saying that civil servants and Christians must leave Bama within seven days or risk being killed, according to one Bama resident speaking to the media on arrival in Maiduguri.

Borno State, of which Maiduguri is the capital, is located in the mainly Muslim north of Nigeria. Southern Nigeria is predominantly Christian.

Ibrahim Aliyu, national director political and social affairs of Christian Association of Nigeria (CAN) youth wing described the situation in Borno State as terrible.

"These people will come to Maiduguri town and attack a school so I think the government should do a lot more than they are doing now," he said.

The insurgents were chased out of their Sambisa Game Reserve camps by the security forces in a crackdown launched on May 14, but some were said to have regrouped and started fresh attacks.

Criticism of the government's handling of the insurgency

Nigeria's military said that a ground and aerial search was being conducted in the hunt for the insurgents who attacked Bama and Gwoza.

This is not the first time that Boko Haram has threatened to attack Christian residents.

Last year, a purported Boko Haram spokesman known by the name of Abul Qaqa, issued an ultimatum to southerners living in the northern part of Nigeria to move away. Abul Qaga was reportedly killed by the Nigerian military last year.

Analyst Ibrahim Shamsudeen accuses the government of President Jonathan of failing to tackle the insurgency adequately. He says there is a confusing scenario in which the government has called for dialogue with Boko Haram, but at the same time it is waging war against them. "If there is going to be a dialogue, let there be circumstances under which these people will come out for dialogue,” he said.

Human right activist Barr Luka Haruna believes the conflict cannot be resolved by military means alone and that despite the declaration of a state of emergency "the government should look seriously to resolving this problem through dialogue.”