A self-driving car operated by Uber struck and killed a woman crossing the street in Tempe, Arizona, overnight, according to local and national media reports. Police have not yet identified the woman. The New York Times reports that the fatality "appears to be the first known death of a pedestrian struck by an autonomous vehicle on public roads."

Police in Tempe say the vehicle was in autonomous mode, though a driver was also behind the wheel, according to ABC 15. (Uber's self-driving technology is not yet technically driverless.)

Uber says it's cooperating with authorities:

Our hearts go out to the victim’s family. We’re fully cooperating with @TempePolice and local authorities as they investigate this incident.
— Uber Comms (@Uber_Comms) March 19, 2018

Some incredibly sad news out of Arizona. We’re thinking of the victim’s family as we work with local law enforcement to understand what happened. https://t.co/cwTCVJjEuz
— dara khosrowshahi (@dkhos) March 19, 2018

The company has reportedly temporarily suspended the self-driving vehicle program today, as it did after another crash in Tempe last year.