SRINAGAR: Four security forces personnel were injured in a grenade attack by suspected terrorists in the Nowhatta area of the city here on Wednesday, police said.Terrorists hurled a grenade on a security forces' party around 9.25 pm at main chowk Nowhatta in the old city area here, a police official said.He said three Sashastra Seema Bal (SSB) personnel and a Jammu and Kashmir policeman were injured in the explosion.Further details are awaited, the official said.