Constable Mehrajuddin, posted on law and order duty at Pampore, was critically injured when the shell went off accidentally in his hand at Drangbal in Pampore town, a police official said.
He was rushed to a nearby hospital where he succumbed to injuries, the official said.
Security forces including police personnel have been deployed in strength to maintain law and order in Pampore town where eight CRPF personnel were killed in a militant attack yesterday.
Two militants were also killed in the retaliatory action by security forces.