Supporters of the BJP and the Trinamool Congress today hurled crude bombs at each other at the Belpata village near Panrui in West Bengal's Birbhum, the police said.
A BJP supporter was admitted to Suri hospital after he sustained splinter injuries.
A huge police contingent from Bolpur rushed to the area to contain the situation.
"The situation is now under control, but we are keeping a close vigil in the area," said a senior police officer.
Meanwhile, a mentally-challenged person assaulted Amarjit Biswas, officer in-charge of Panrui police station, with a screw driver during a raid in the village.
Biswas, however, escaped unhurt, the police said, adding that the man was briefly detained but released later.