The US firefighter who ran over and killed a survivor of the Asiana Airlines crash in San Francisco was unaware she was responsible for the girl's death at the time of the incident.
San Mateo County District Attorney Steve Wagstaffe said on Friday that the firefighter was responding to the burning Boeing 777 when the truck she was driving unknowingly rolled over Ye Mengyuan.
Investigators believe Ye was laying prone on the tarmac and covered in firefighting foam.
Wagstaffe said Duckett would not be charged criminally.
The San Francisco Fire Department chief declined to discuss the 16-year-old's death, but said in a prepared statement that firefighters likely saved the lives of many critically wounded passengers.
In all, 304 of the 307 people aboard the Boeing 777 survived the July 6 crash.