Two traffic cops, including an assistant sub-inspector, and two civilians were injured in a powerful hand grenade explosion in the Batmaloo locality of Srinagar on Monday evening.
A senior police officer said terrorists lobbed a grenade at a police party near the fire services headquarters in the locality, which exploded on the road.
"Two traffic cops, an assistant engineer of the state roads and buildings department and another civilian were injured in the explosion. They were immediately taken to hospital where condition of the engineer is stated to be critical," the officer said.
The explosion triggered panic in the area, which was later searched by the security forces.
Earlier in the day, terrorists killed a shopkeeper in the Kreeri town of north Kashmir's Baramulla district.
Police said terrorists fired pistol rounds at Nazir Ahmad Lone from a close range in Kreeri market. Lone was rushed to Srinagar for specialised treatment. He, however, succumbed to injuries in the evening