Additional SP Abhisek Modi said the ASI Mrinal Kanti Mallick had to be given five stitches on his head after being hit by a bamboo pole when a police force went to the area on getting information about land dispute between two neighbours in the area.
A civic police volunteer was also injured but discharged after first aid.
The ASP said Mallick had to be referred to Malda Medical College and Hospital.
A big police force went to the area.