**A group of Nigerian Islamist militants is barricaded into a small area in the city of Maiduguri after two days of violence in the country’s north.**A BBC reporter in the city says the Islamists are shooting at anyone coming close to their stronghold.
President Umaru Musa Yar’Adua had ordered the security forces to use all necessary means to end the violence, in which at least 100 have died.
The militants wants Islamist rule and an end to Western education.
One group is now under siege by the security forces, in an area including a mosque and the home of their leader Mohammed Yusuf in Maiduguri.
Mr Yusuf says young people in the region are being corrupted by the West, and by Western education.
His followers are known as Boko Haram, which means “Education is prohibited”.
ANALYSIS
By Caroline Duffield, BBC News, NigeriaTensions are never far from the surface in northern Nigeria. Poverty and competition for scarce resources, along with ethnic, cultural and religious differences have all fuelled sudden violence.
But the latest violence is not between communities, it involves young men from religious groups, arming themselves and attacking local police.
Fringe religious groups in Nigeria have claimed links to the Taliban before - individuals have also been accused of links to al-Qaeda. But Nigeria is very different to countries like Mali or Algeria, where groups such as al-Qaeda in the Islamic Maghreb operate.
The idea of radical Islamist militants gaining a serious foothold in Nigeria is usually dismissed, because of the strength of local identities and traditions.
The Nigerian military has stepped up security following the clashes.
Soldiers have set up road blocks and imposed dusk-to-dawn curfews in the worst affected areas of Yobe, Kano and Borno States.
Islamist militants staged attacks on police and government offices.
There have been reports of youths armed with machetes and guns killing police officers and civilians at random.
Eyewitnesses told the BBC that police stations had been attacked and civilians pulled from their cars and shot dead.
Maiduguri in Borno State, has seen the worst violence. The bodies of residents and militants have been piled outside the police station and in the streets.
A BBC reporter there counted 100 corpses.
Earlier, witnesses told the BBC that a battle had raged for hours in Potiskum, Yobe State, where a police station and neighbouring buildings were reportedly razed.
There were also attacks on police in Wudil, some 20km (12 miles) from Kano, the largest city in northern Nigeria.
Security is said to have been particularly beefed up in Plateau State, to the south of Bauchi, where hundreds were killed in clashes between Muslims and Christians last year.
Nigeria’s anti-education preacher
Youths began attacking police stations in Bauchi on Sunday after some of the group’s leaders were arrested.
Correspondents say Boko Haram has aroused suspicion for its recruitment of young men, and its belief that Western education, culture and science are sinful.
Reuters news agency reports that one of the group’s leaders, arrested in Kano state, said his followers were standing up for their faith.
“Even if I’m arrested, there are more to do the job,” Abdulmuni Ibrahim Mohammed is quoted as saying.
Sharia law is in place across northern Nigeria, but there is no history of al-Qaeda-linked violence in the country.
The country’s 150 million people are split almost equally between Muslims and Christians and the two groups generally live peacefully side by side, despite occasional outbreaks of communal violence.
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