accused of insulting the prophet Mohammed.
An AP reporter watched protesters throw blazing, fuel-filled tires into the building then start 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.Religion is the cause of much violence in Nigeria, but generally involves Christians and Muslims. A multinational force is curbing a nearly 6-year-old Islamic uprising by extremists who would impose Shariah law across Nigeria.
A moderate version of Shariah is practiced alongside Western-style justice in the mainly Muslim northern states.