The Pakistani capital Islamabad has been rocked by another fatal assault just two days after twin suicide bombings at a university.This time the target was an army brigadier, who was shot dead in his car along with his driver by gunmen on motorcycles. It is not clear who carried out the attack but it comes amid a military operation against the Taliban. On Saturday some 25,000 Pakistani soldiers launched their offensive in the militants’ frontier stronghold in Waziristan. Later on Thursday there were reports of gunfire at a courthouse in Islamabad but officials now say this was a false alert. Tension is high and schools remain closed in towns across Pakistan where a string of bombings and shootings have killed more than 150 people in the last two weeks.