US forces have all but wiped out an alleged al-Qaeda linked group in northern Iraq with help from their Kurdish allies - and Iranians who have sealed off the Islamist militants' only exit. US special forces set out today from Halabja in Iraqi Kurdistan with Kurdish fighters to track down militants of the Ansar al-Islam group who might have survived the bombing and the onslaught on their stronghold. The US forces kept mum on the location of their hunting ground, but a Kurdish official said it was a mountainous region on the border with Iran because "they have nowhere else...