Senior Superintendent of Police Prahlad Meena said the madrasa and the mosque stood on an illegally encroached government land and the demolitions were carried out in the heavy presence of police and Provincial Armed Constabulary (PAC) personnel in compliance with a court order.
Angry residents, including women, in large numbers descended on the streets to protest the action as the demolition of the two structures began.
They were seen breaking barricades and arguing with the police personnel engaged in the demolition exercise.
As a bulldozer razed the madrasa and the mosque, mobs hurled stones at the police personnel, municipal corporation workers and journalists, officials said.
The police tried to disperse the irate mob by resorting to a mild lathi charge and bursting of teargas shells.
However, tension escalated with the mob setting fire to several vehicles, including a police patrol car, they said.
By late evening, tension mounted further and the Banbhoolpura Police Station was also set on fire, leading to imposition of curfew in the town, they added.
The injured people have been admitted to the Soban Singh Jeena Hospital here, the officials said, adding that a majority of them suffered injuries on their heads and faces.