The U.S. military in Afghanistan is investigating the cause of Thursday's blast near an ammunition dump that left seven soldiers dead, one missing and three people injured. U.S. authorities say there are no indications at this time there was enemy activity near the site of the incident.
U.S. military officials have not yet determined the cause of the explosion, which took place at an ammunition dump near the southern Afghan town of Ghazni.
The seven soldiers killed in the incident were working near the arms cache. Those wounded have been evacuated to a hospital at the U.S.-controlled Bagram Air Base near the capital, Kabul.
The incident is being described as one of the deadliest blows to U.S. anti-terrorism forces since they launched operations in Afghanistan two years ago.
Five U.S. military personnel were killed in November when their helicopter crashed northeast of Kabul.