Death Toll Expected To Rise

Around a dozen soldiers, police officers and prison officials are among the hundreds killed in the unrest, while the remainder of the dead largely consist of suspected Boko Haram followers, according to police.

Members of a local Islamic group sit after their arrest in Kano July 27, 2009. [Agencies]

National defence spokesman Colonel Mohammed Yerima said there would be a military "show of force" on Friday to reassure civilians that they would be protected.

He said all criminal suspects had a right to due process, and Nigerian authorities must investigate the killing and hold those responsible for it accountable.

Yusuf's death also deprives intelligence agencies of the opportunity to question him about possible links to other militant groups outside Nigeria.

President Yar'Adua, on an official visit to Brazil, spoke by telephone with northern governors on Thursday and urged traditional and religious leaders to use Friday prayers to warn people about the dangers of such sects.

Boko Haram's views are not espoused by the majority of Nigeria's Muslim population, the largest in sub-Saharan Africa. The country's Muslim umbrella group, Jama'atu Nasril Islam, has already condemned the violence.