Police have confirmed previous reports that one of the two teenage girls killed in the San Francisco plane crash was indeed run over by a fire truck. But it's still unclear whether that's what actually killed 16-year-old Ye Meng Yuan, the San Francisco Chronicle reports. "The passenger was underneath the fire retardant foam and when the fire truck repositioned itself to battle the flames aboard the fuselage, the passenger victim was discovered in the tire track of the fire truck," says a police spokesperson, per Reuters. "It is unknown if the passenger was deceased at the time or if the passenger died as a result of the fire truck going over the victim." The San Mateo county coroner will release a report with the cause of death in two weeks.