PESHAWAR  - At least seven children were injured when a Grenade blast detonated in Darra Adamkhel near Kohat on Tuesday.Darra Adamkhel is located between Peshawar and Kohat.Eyewitnesses said that the blast was very intense and it could be heard from a long distance. The children were taken to Lady Reading Hospital Peshawar. The children received severe injuries and some of them were in a critical situation, hospital sources said.