Watch: Google’s Self-Driving Car Strikes Public Bus in California

The self-driving car could not gauge the speed at which the bus was moving.

Alphabet Inc’s Google self-driving car struck a municipal bus in a minor crash – in what may be the first case of one of its autonomous cars hitting another vehicle. In a February 23 report filed with California regulators, Google said the February 14 crash took place in Mountain View, California, when a self-driving Lexus RX450h sought to get around some sandbags in a wide lane.

Google has said in the filing, the autonomous vehicle was traveling at less than 2 miles per hour while the bus was moving at about 15 miles per hour. The vehicle and the test driver “believed the bus would slow down or allow the Google (autonomous vehicle) to continue,” it said.

But three seconds later, as the Google car in autonomous mode re-entered the center of the lane, it struck the side of the bus, causing damage to the left front fender, front wheel and a driver side sensor. No one was injured in the car or on the bus.

Google said in a statement that “we clearly bear some responsibility, because if our car hadn’t moved, there wouldn’t have been a collision. That said, our test driver believed the bus was going to slow or stop to allow us to merge into the traffic, and that there would be sufficient space to do that.”

Google said it has reviewed this incident “and thousands of variations on it in our simulator, in detail and made refinements to our software.

The crash comes as Google has been making the case that it should be able to test vehicles without steering wheels and other controls.