Four Iraqi national guards have been killed and at least 80 injured in a major attack on their headquarters north of the capital, Baghdad. Iraqi officials and the US military said insurgents fired several mortar rounds at the building in Mushahida, 40km (25 miles) from the Iraqi capital. US helicopters helped ferry the injured to two military field hospitals. Iraq’s fledgling security forces are a frequent target for militants opposed to the US-backed government. Full Story