Self-driving Uber strikes and kills pedestrian

Uber has halted testing of its autonomous vehicles across North America, the company announced, after a woman was struck and killed by one of its self-driving cars in Tempe, Ariz. early Monday.

The moratorium on testing includes San Francisco, Phoenix, Pittsburgh and Toronto, Uber said.

The National Transportation Safety Board has opened an investigation into the crash, said Eric Weiss, a spokesman for the NTSB.

Uber issued a short statement.

"Our hearts go out to the victim's family. We are fully cooperating with local authorities in their investigation of this incident," a company spokeswoman said.

Uber CEO 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're thinking of the victim's family as we work with local law enforcement to understand what happened."