A roadside bomb ripped through a crowded bus in Afghanistan today, killing up to 25 civilians. The bomb exploded as the bus travelled on a highway through Nimroz province. Provincial governor Ghulam Dastgir Azad said, although there was no claim of responsibility, officials blamed the attack on the Taliban, which is fighting to overthrow the Afghan government and evict nearly 150,000 foreign troops in a nine-year insurgency. Mr Azad said more than 20 civilians were killed in the blast. The interior ministry in Kabul put the death toll at 25 with more than 20 others injured.