A spokesperson for Waymo said that its auto was struck when "another vehicle traveling in an oncoming lane swerved across the median".
Chandler police confirmed that the Waymo vehicle was in autonomous mode with a human backup driver behind the wheel at the time of the crash.
The Chrysler Pacifica equipped with Waymo's self-driving technology was struck by a Honda Civic heading in the opposite direction that had swerved to avoid a third auto that had run a red light.
Police said the vehicle that ran the red light was extended a ticket to the moving violation. Police in Chandler, Arizona, said that the Waymo van was not the "violator vehicle" in the crash. "We are concerned about the well-being and safety of our test driver and wish her a full recovery".
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Reported six dead and 30 wounded, but it is unclear whether there are among them representatives of the top of the Houthis. One resident says he saw a body fly over a shop and a auto washer killed by shrapnel.
Photos taken at the scene show significant damage to the driver's side of the Waymo van and the front of a silver Honda sedan, with pieces of both vehicles scattered across the roadway. It released a video of the moments before the collision.
By contrast, Google's Waymo disengaged, or required human intervention during autonomous driving, every 5,600 miles.
Police in a Phoenix suburb are investigating a collision involving a self-driving vehicle owned by the company Waymo.
The safety of self-driving technology has come under scrutiny in recent months. The company has also teamed up with bus maker King Long United Automotive Industry to produce China's first fully autonomous bus.