Although not the first time one of Google's self-driving cars has been involved in a collision, the Valentine's Day crash on a public street in Mountain View, California may be the fist time such an incident was the fault of the software at the car's helm. While an accident report filed by Google doesn't explicitly admit robot culpability, a statement issued today by the company acknowledges the software to be at least somewhat to blame.

The report details the collision on El Camino Real, which apparently happened as the self-driving car attempted to avoid some sand bags in the road, and further notes that yes, a "Google AV test driver" AKA "human" was in the car at the time — but was not in control.

After a few cars had passed, the Google AV began to proceed back into the center of the lane to pass the sand bags. A public transit bus was approaching from behind. The Google AV test driver saw the bus approaching in the left side mirror but believed the bus would stop or slow to allow the Google AV to continue. Approximately three seconds later, as the Google AV was reentering the center of the lane it made contact with the side of the bus. The Google AV was operating in autonomous mode and traveling at less than 2 mph, and the bus was traveling at about 15 mph at the time of contact.

The car in question was a Lexus model (not one of those adorable, custom-designed Google cars), and no one was injured in the crash. The Associated Press reports that the DMV hopes to speak with a Google representative today, but as of press time had yet to do so.

A brief statement issued today by Google, and reported by Re/code, claims that "[this] type of misunderstanding happens between human drivers on the road every day" and further notes that "[in] this case, we clearly bear some responsibility, because if our car hadn’t moved there wouldn’t have been a collision."

According to a monthly Google-issued report, as of January 31 the company had 22 Lexus RX450h SUV's in operation on public streets and its cars had logged close to 1.5 million miles in "autonomous mode."

Related: Self-Driving Cars Will Still Need A Human Driver, Say DMV Draft Rules