Protesters threw lit fuel-filled tires into the building then started marching through streets to demand punishment for Malam Abdul Nyass.
Police monitored the crowd, which turned peaceful after the fire.
Nyass is accused of saying that the long-dead leader of the Tijanniyah sect is more powerful than the revered prophet Muhammad. Kano's mainly Muslim population adheres in almost equal numbers to the Sunni and Tijanniyah sects of Islam.
Police arrested Nyass when Muslims threatened to kill him after the alleged insult. He appeared before the Shariah court but was apparently secretly freed and is in hiding.
Posts
