At least 36 people have been killed in two separate attacks in Pakistan. A suspected car bomb exploded in the northern town of Peshawar. It destroyed a school bus, killing four children. Dozens more people were wounded.The blast came as the Pakistan army continues its assault against the Taliban in the Swat Valley. The military has been ordered to crush the militants, and the car bomb may be a reaction to the offensive. Hundreds of thousands of refugees have fled the fighting in Swat. The United Nations has warned of a looming humanitarian tragedy. At the same time as the Peshawar bomb, news came of an attack on a suspected militant base near the Afghan border. An US drone aircraft fired missiles which are believed to have hit an ammunition dump. At least 25 people are reported dead. The surge in violence has led many Pakistanis to question their government’s security ties to the United States.