Uber is shutting down testing of self-driving cars in Arizona after one of its cars killed a pedestrian in a March crash. In an internal email, Uber executive Eric Meyhofer wrote that Uber would be shifting its focus to Pittsburgh, where the company has been testing self-driving cars since 2016, and San Francisco, where Uber is headquartered.

Uber's testing program has been grounded nationwide since the March crash, but until now it wasn't known how long it would take to get back up and running. Uber hopes to resume testing in Pittsburgh this summer.

Meyhofer also indicated that Uber would be changing how it tested its driverless cars. "When we get back on the road, we intend to drive in a much more limited way to test specific use cases," Meyhofer wrote. "Taking this approach will allow us to continually hone the safety aspects of our software and operating procedures. We have also used the past two months to strengthen our simulation capability, which will allow us to be more efficient with our use of road miles."

About 200 Uber employees in Arizona—many of them safety drivers—will lose their jobs, the Arizona Republic reports.

Meyhofer's full email is reproduced below.

Team, We’ve made the tough call to wind down operations in Phoenix. As you know, there’s been a public call for the suspension of our self-driving program on Arizona's public roads and we have decided to refocus the bulk of our efforts in our engineering hubs in San Francisco and Pittsburgh. This is the best path forward as we work to get back on the road as soon as possible. To be clear, we are not shutting down our self-driving program. We are actively working to make our return to the road a reality with a goal of resuming operations in Pittsburgh this summer. We are also in conversations with the California Governor, California DMV and cities of San Francisco and Sacramento. When we get back on the road, we intend to drive in a much more limited way to test specific use cases in concert with our Software and Hardware development teams. Taking this approach will allow us to continually hone the safety aspects of our software and operating procedures. We have also used the past two months to strengthen our simulation capability, which will allow us to be more efficient with our use of road miles. Our return to public roads is tied to securing the proper testing permits alongside our safety improvements. We remain focused on our safety review, which is evaluating everything from the safety of our system to our vehicle operator training. We’ll be sharing the following media statement: “We’re committed to self-driving technology and look forward to returning to public roads in the coming months. In the meantime, we remain focused on our top-to-bottom safety review, having brought on former NTSB Chair Christopher Hart to advise us on our overall safety culture.” I appreciate your staying the course during this difficult time and truly believe that together we can realize the potential of this technology. -Eric

Cyrus Farivar contributed reporting for this story.