Arizona Woman Hit by Uber’s Self-Driving Car May Be First Pedestrian Killed by an Autonomous Vehicle

The death of an Arizona woman who was struck by one of Uber’s self-driving cars appears to be the first ever pedestrian fatality involving an autonomous vehicle.

An Uber spokesperson confirmed to TIME that the incident occurred Sunday night in the Phoenix suburb of Tempe and that no passengers were in the backseat. Uber said there was one vehicle operator in the front seat at the time of the collision. The company says it’s suspending its self-driving operations in Phoenix, Pittsburgh, San Francisco and Toronto as a result.

In a statement, the Tempe Police Department confirmed the vehicle involved was one of Uber’s driverless cars and that it was in autonomous mode at the time of the accident. “The vehicle was traveling northbound just south of Curry Rd. when a female walking outside of the crosswalk crossed the road from west to east when she was struck by the Uber vehicle,” the statement read. “She was transported to a local area hospital where she passed away from her injuries.”

Uber has been testing its self-driving program for years, notably in Pittsburgh, where it rolled out its first driverless fleet in 2016. Autonomous vehicles generated controversy that same year when a passenger operating a Tesla Model S in “autopilot mode” died in a crash in Florida, but Uber’s incident is likely the first time a bystander not driving the car was killed by the technology.

Uber CEO Dara Khosrowshahi addressed the incident in a tweet Monday afternoon. “Some incredibly sad news out of Arizona,” he wrote. “We’re thinking of the victim’s family as we work with local law enforcement to understand what happened.”

Authorities have not yet released the victim’s identity and her next of kin has not yet been notified, the Temple PD said.