Police in a suburb of Phoenix say a self-controlled Waymo vehicle was among the five cars involved in a collision, but no serious injuries were reported.
The Waymo vehicle driver told Mesa police that the car was not in stand-alone mode at the time of Saturday night's accident.
Witnesses reported that another car was not stopped by a red light and crashed into the Waymo vehicle. it turned to the left.
The car collided with three other vehicles.
Waymo, whose parent company is Google, did not immediately return a message seeking comment on Sunday.
Vehicles that drive cars have been attacked as a Uber vehicle in standalone mode with an operator behind the wheel fatally struck a woman in nearby Tempe.
A Waymo vehicle was hit by a red light corridor last month in the Phoenix suburb of Chandler.