Pennsylvania authorities have given Uber permission to resume road testing in Pittsburgh, after a series of accidents involving their self-driving cars halted Uber’s autonomous car pilot project. Although the ban, which had been implemented in Pennsylvania, Arizona and California, has not been lifted in any other cities, Uber aims to restart testing in San Francisco and begin new manual road tests in Toronto.

A week before approval from Pennsylvania was given, The Information revealed that an “alarming” email had been sent to Eric Meyhofer, head of Uber’s autonomous vehicle unit, stating the cars had major safety issues back in March. The email came from Robbie Miller, a manager in the testing-operations group, claiming the “software powering the company’s prototype robotaxis was dangerous.” Five days after the email was originally sent to Meyhofer, an Uber self-driving car prototype killed a pedestrian during a road test in Arizona.

Uber’s top legal officer, Tony West, admitted he did not know why Uber did not immediately suspend testing of the self-driving cars when Miller’s email was sent, but claims the unit has added new and improved safety features to vehicles since the collision.

The fatality was not the first accident involving an Uber self-driving car. In March of 2017, a self-driving car carrying two Uber engineers collided with another vehicle in Tempe, Arizona. No injuries were reported, and the Tempe Police Department concluded the Uber car was not at fault. It was unclear if the car was in auto-pilot mode or controlled by the engineers.

It was reported by The Information that Uber spent $80m on its self-driving car program in the second quarter of 2017, increasing to $120m in the second quarter of 2018 alone.