Churches and government buildings have been torched by groups of militants who have been dubbed Nigeria's Taliban.

The unrest is the deadliest sectarian violence in Nigeria since November last year when human rights groups say up to 700 were killed in Muslim-Christian clashes in and around the central city of Jos.

The current death toll, according to reports, has exceeded 150.

The clashes, which erupted on Sunday, have so far been contained to four northern Muslim states in Africa's most populous nation.

President Umaru Musa Yar'Adua, himself a Muslim from the north, ordered security forces on maximum alert in a decree issued late Monday.

According to the decree, the president "ordered national security agencies to take all necessary action to contain and repel the sad and shocking attacks by extremists."

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"After being briefed today by the heads of the security agencies on the violent attacks in parts of Bauchi, Borno, Kano and Yobe states, President Yar’Adua directed that no effort should be spared in identifying, arresting and prosecuting leaders and members of the extremist sects involved in the attacks," the statement read.

"The President further directed that security be beefed up in all neighbouring states and security personnel placed on full alert to ensure that the attacks by misguided elements do not spread elsewhere," it added.

"President Yar’Adua reaffirms his determination to deal decisively with all those whose misguided beliefs and actions promote violence and contempt for the rights of others, while undermining national peace, stability and security."