The policemen on patrol were attacked when they tried to intercept the van in which the assailants were travelling, they said, adding the attackers fled the scene and abandoned the vehicle at Varakala, about 20 km from the crime scene.
The deceased was identified as Manian Pillai (47), a constable of Paripally police station.
Joy, the injured ASI, has been admitted to a hospital here in a serious condition.
An intense search has been launched to nab the assailants based on some evidence obtained from the van, including the registration book, police said.
Patrolling had been stepped up in the area recently after several cases of burglary were reported.
