Nvidia Corp said on Tuesday it has suspended self-driving tests across the globe, a week after an Uber Technologies Inc autonomous vehicle struck and killed a woman crossing a street in Arizona.

Uber is one of Nvidia’s partners using the technology. Nvidia’s shares closed down 7.8 percent at $225.52, wiping out more than $11 billion in market value.

Uber suspended North American tests of its autonomous vehicles after the fatal collision on March 18 in Tempe, Arizona. And Arizona on Monday suspended permission for Uber to test self-driving vehicles on public streets. This has not stopped them from ramping up research to ensure the safety of such technology.