The deaths bring to 55 the number of US troops killed in October in Afghanistan.

The previous record high was in August, when 51 US soldiers died as Afghanistan held the first round of its presidential election. The Taliban had threatened to disrupt the poll, which has now gone to a second round run-off after widespread fraud was revealed.

The deadliest month for US troops in Iraq was November 2004, when 137 US soldiers were killed during the assault on the city of Fallujah.

Tuesday's deat...