The National Highway Traffic Safety Administration said Thursday it is opening an investigation after a Waymo self-driving vehicle struck a child near an elementary school in Santa Monica, California last week, causing minor injuries.

The auto safety agency said the child ran across the street on Jan. 23 from behind a double parked SUV towards the school and was struck by the Alphabet-unit Waymo autonomous vehicle during normal school drop off hours.

The agency said there were other children, a crossing guard, and several double-parked vehicles in the vicinity.

Waymo said in a blog post Thursday it will cooperate in the investigation and said the child "suddenly entered the roadway from behind a tall SUV, moving directly into our vehicle's path" and added the self-driving vehicle immediately detected the individual as soon as the child began to emerge from behind the stopped vehicle, braking hard and reducing speed from approximately 17 mph to under 6 mph before contact was made.

NHTSA is opening a preliminary evaluation to investigate whether the Waymo AV exercised appropriate caution given its proximity to the elementary school during drop off hours, and the presence of young pedestrians and other potential vulnerable road users.

The agency said it plans to examine the vehicle's "intended behavior in school zones and neighboring areas, especially during normal school pick up/drop off times, including but not limited to its adherence to posted speed limits" and will "also investigate Waymo's post-impact response."

Waymo said a computer model suggested a fully attentive human driver in this same situation would have made contact with the pedestrian at approximately 14 mph. After the collision, the child stood up immediately, walked to the sidewalk, and Waymo called 911.

"The vehicle remained stopped, moved to the side of the road, and stayed there until law enforcement cleared the vehicle to leave the scene," Waymo said.

The same day as the incident, the National Transportation Safety Board opened an investigation into Waymo after its robotaxis illegally passed stopped school buses in Austin, Texas, at least 19 times since the start of the school year.

Waymo in December recalled more than 3,000 vehicles to update the software that had caused vehicles to drive past stopped school buses that were loading or unloading students, increasing the risk of a crash.

NHTSA opened a probe in October into Waymo vehicles near school buses.

Waymo said Friday there were no collisions in the incidents. The Austin Independent School District said in November five incidents occurred in November after Waymo software updates to resolve the issue.

The school system asked the company to halt operations around schools during pick-up and drop-off times until it could ensure the vehicles would not violate the law.

In December, the school district told Reuters that Waymo had refused to halt operations around schools.