One of Uber's self-driving vehicles has struck and killed a pedestrian in a suburb of Pheonix, Arizona, police said.
Officers in Tempe said the vehicle was in autonomous mode with an operator behind the wheel when the woman was struck.
The woman, whose name has not yet been released, died of her injuries in hospital.
Uber has been testing the self-driving vehicles in Tempe and Phoenix for months.
Police said Uber is co-operating in the investigation.