Toyota has suspended tests of its “Chauffeur” autonomous driving system following the deadly collision between a self-driving Uber prototype and a pedestrian in Arizona.

In an emailed statement issued to Bloomberg, the Japanese automaker said the decision has been made for the emotional health of its test drivers.

“Because we feel the incident may have an emotional effect on our test drivers, we have decided to temporarily pause our Chauffeur mode testing on public roads,” spokesman Brian Lyons said.

Toyota has been conducting self-driving tests in Michigan and California but unlike most of its rivals, has failed to disclose just how many prototypes it is currently operating.

The deadly Uber crash occurred just a few days after reports surfaced that Toyota and Uber were looking to collaborate on autonomous driving systems. Details of a potential partnership are few and far between but last week, a Toyota spokesman said no decision has been made as to whether or not the brand will purchase Uber’s autonomous software.

Furthermore, Lyons confirmed that Toyota “does not have first-hand information on the tragic traffic fatality.”

According to police, the crash involving the Uber prototype occurred when the vehicle was in autonomous mode and had a safety driver behind the wheel.