Kabul, Afghanistan ? A road crash that triggered deadly anti-American rioting in Kabul occurred because a military truck lost its brakes coming down a hill and plowed into a line of cars, the U.S. military said Tuesday.

Chanting “Death to America,” rioters on Monday stoned the U.S. convoy involved in the accident, then headed to the center of Kabul, ransacking offices of international aid groups and searching for foreigners. Smoke billowed from burning buildings.

The death toll from the unrest rose to 11, most of them from gunshot wounds, according to three city hospitals. More than 100 people were wounded.

Up to five people were killed in the accident, but it wasn’t clear whether these deaths were among the tolls the hospitals reported.