Two Waymo autonomous vehicles drive themselves down Central Avenue in Phoenix, Arizona, U.S., March 18, 2024. /Reuters

The National Highway Traffic Safety Administration (NHTSA) is seeking more information about incidents involving Alphabet's Waymo self-driving vehicles. In May, the agency launched an investigation following 22 reports of the company's robotaxis exhibiting unsafe driving behaviors, including 17 collisions.

The U.S. auto safety regulator said on Wednesday that there were several incidents where Waymo vehicles collided with clearly visible objects that competent drivers would avoid. It said that Waymo is to respond by August 6 with details of all travel on public roads by the company's driverless vehicles, as well as any updates or testing conducted to address specific incidents.

NHTSA expressed concerns that Waymo's unexpected driving behaviors could increase the risk of crashes, property damage and injuries, especially near pedestrians and other road users. This investigation follows similar probes into self-driving vehicles by General Motors' Cruise and Amazon's Zoox.

Earlier this month, Waymo stated it was "proud of our performance and safety record over tens of millions of autonomous miles driven." In February, Waymo recalled 444 self-driving vehicles after two minor collisions in Arizona due to a software error.

(With input from agencies)