THREE people were killed in clashes on Tuesday in the far northern Nigerian city of Sokoto over demands for the imposition of Islamic Sharia law, reports said. Two churches were burnt down in the clashes which broke out around the university, one resident who asked not to be identified said. Details of the unrest — the first in Sokoto over the explosive Sharia issue — are extremely sketchy. A Nigerian journalist said tension in this city of more than two million people is high, and sporadic gunfire could be heard during the day. Demands by Muslims in the northern city of Kaduna for the Islamic code to be introduced have led to two weeks of unrest in which around 1000 people have died.