A grenade attack by terrorists on a police station in north Kashmir on Srinagar – Uri road left seven people, injured including four police personnel wounded last night, official sources said in Srinagar.The grenade attack came 24 hours after a high-level Core Group meeting was held at the headquarters of 15 Corps to discuss sudden increase in the militant attacks in the Kashmir valley.A massive hunt has been launched to nab the attackers. This was the sixth such attack in the Valley during the past two weeks.