Dozens of people have been killed after Islamist militants staged three attacks in northern Nigeria, taking the total killed in two days of violence to 150.
A Report:
Tensions 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.
By Caroline Duffield, BBC News, Nigeria
Some of the militants follow a preacher who campaigns against Western schools.
The preacher, Mohammed Yusuf, says Western education is against Islamic teaching.
There has also been an attack in Wudil, some 20km (12 miles) from Kano, the largest city in northern Nigeria.
A curfew is in force in Bauchi, the scene of Sunday's violence.
Sharia law is in place across northern Nigeria, but there is no history of al-Qaeda-linked violence in the country.Sharia law is in place across northern Nigeria, but there is no history of al-Qaeda-linked violence in the country. 
Source BBC News
