All schools and colleges have also been closed in the city, they said.
During the clash, which took place on Sunday night in Shahbad area, people indulged in stone-pelting, firing and arson. Later it spread to some other areas of the city and some persons set fire to a vegetable market in Sahmatganj and some shops in Jogi Nawada area, officials said.
The injured were rushed to hospital, where one Imran of Rolitola in Baradari area died due to gun shot injuries, they said.
Divisional commissioner K Rammohan Rao said that curfew has been imposed in the entire city and all schools and colleges have been closed till further orders.
"The situation is under control and no fresh incident was reported from anywhere in the city. Elaborate security arrangements have been made," district magistrate Manish Chauhan said.
Additional director general (law and order) Jagmohan Yadav has reached the city to take stock of the situation.
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