TEMPE (Arizona) • Ride-hailing company Uber has abruptly halted testing of its autonomous vehicles across North America after a 49-year-old woman was struck and killed by one of its cars while crossing a street in Tempe, Arizona.
The moratorium on testing announced on Monday includes San Francisco, Phoenix and Pittsburgh in the United States, and Toronto in Canada.
The National Transportation Safety Board has opened an investigation into the crash, said spokes-man Eric Weiss.
Ms Elaine Herzberg, 49, was walking her bicycle outside the crosswalk on a four-lane road in the Phoenix suburb of Tempe at about 10pm on Sunday when she was struck by the Uber vehicle travelling at about 65kmh, police said.
The Volvo XC90 SUV was in autonomous mode with an operator behind the wheel.
Ms Herzberg later died from her injuries in hospital, police said.
"The pedestrian was outside of the crosswalk. As soon as she walked into the lane of traffic, she was struck," Tempe police sergeant Ronald Elcock told reporters at a news conference.
He said he did not yet know how close Ms Herzberg was to the vehicle when she stepped into the lane.
Sgt Elcock said he believed Ms Herzberg may have been homeless.
The San Francisco Chronicle reported late on Monday that Tempe police chief Sylvia Moir said that from viewing videos taken from the vehicle, "it is very clear it would have been difficult to avoid this collision in any kind of mode (autonomous or human-driven), based on how she came from the shadows right into the roadway".
She told the Chronicle "it appears that the Uber would likely not be at fault in this accident", but she did not rule out that charges could be filed against the operator in the Uber vehicle, the paper reported.
Uber chief executive officer Dara Khosrowshahi said in a tweet that the company was working to learn what went wrong.
"Some incredibly sad news out of Arizona," he said. "We are thinking of the victim's family as we work with local law enforcement to understand what happened."
Uber and its rival Waymo last Friday urged Congress to pass sweeping legislation to speed up the introduction of self-driving cars in the US.
Some congressional Democrats have blocked the legislation over safety concerns, and Sunday's fatality could hamper passage of the Bill, congressional aides said on Monday. Safety advocates called for a national moratorium on all robot car testing on public roads.
Concerns over the safety of autonomous vehicles flared after a July 2016 fatality involving a Tesla car with a partially autonomous system that required human supervision. Safety regulators later determined Tesla was not at fault.
Sunday's crash was not the first involving Uber's self-driving vehicles, nor its first in Tempe. Last March, the company temporarily suspended its self-driving fleet after a Volvo XC90 overturned when another driver failed to yield, according to Tempe police.
The authorities said Uber, which had a backup driver, was not at fault. But it was the first major accident involving the company's self-driving fleet.
Many major carmakers - General Motors, Ford, Toyota, Volvo and Tesla among them - are at various stages of developing, deploying and testing autonomous vehicle technologies.
Boston-based and Singapore Government-funded nuTonomy has been testing driverless vehicles at one-north, a research and development hub in Buona Vista, since April 2016, with plans to roll out driverless taxis here by the middle of this year.
In October 2016, a self-driving car hit a lorry in Biopolis Drive while on a test drive.
WASHINGTON POST, REUTERS