The United States says it will help Pakistan pursue the terrorists responsible for a grenade attack at a Protestant church used by foreigners.

Pakistan put its military and police on high alert today and stepped up security at diplomatic missions and churches after a grenade attack on a Protestant congregation killed five people.

Police in Pakistan were today trying to identify a body that they believe could be the attacker who launched the grenade attack on an Islamabad church, killing five people and injuring more than 45, including five Britons.