The Indian army has been called into Ahmadabad after 20 people were killed in sectarian violence during a strike called by Hindu nationalists.
Narendra Modi, chief minister of the western state of Gujarat, says the army has been brought in to assist the civil administration.
Violence began when Muslim tea vendors and their neighbours stoned a train carrying Hindu nationalists returning from a religious site disputed by Hindus and Muslims.
After slogan-chanting Hindu nationalists refused to pay for snacks during a five-minute halt, the mob set the train on fire, killing 58, the rail station chief, J.K. Katija, said.
Hindu nationalists called for a statewide strike in retaliation for the deaths and angry mobs rioted and looted shops in the commercial capital and other Gujarat towns.