Sgt. 1st Class Michael Goble was with his unit when its members discovered an undisclosed amount of Taliban weapons in Kunduz province, said Eric Pahon, a spokesman for the U.S. forces in Afghanistan.
Pahon said Goble and others were clearing out the cache when an explosion happened.
Pahon said the Taliban wrongly claimed that the service members were in a convoy and targeted by a roadside bomb during a raid.
Goble, 33, of Washington Township in Bergen County, New Jersey, was killed Monday and an Afghan service member was wounded. Goble served with the 1st Battalion, 7th Special Forces Group.
Details about what type of weapon or ammunition exploded are still under investigation.