A Waymo driverless vehicle at Bronx Community College in the Bronx Borough of New York City , U.S., October 16, 2025. REUTERS/Shannon Stapleton

By David Shepardson

WASHINGTON, Dec 4 (Reuters) - A U.S. agency said on Thursday it has asked Waymo to answer more questions after Texas officials said the Alphabet unit's self-driving vehicles had illegally passed school buses 19 times since the start of the school year.

The National Highway Traffic Safety Administration opened a probe in October after an incident in Georgia in which a Waymo did not remain stationary when approaching a school bus with its red lights flashing and stop arm deployed.

In a November 20 letter posted by NHTSA, the Austin Independent School District said five incidents occurred in November after Waymo said it had made software updates to resolve the issue and 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.

Waymo did not immediately respond to a request for comment.

"We cannot allow Waymo to continue endangering our students while it attempts to implement a fix," a lawyer for the school district wrote, citing one incident involving a Waymo "recorded driving past a stopped school bus only moments after a student crossed in front of the vehicle, and while the student was still in the road."

A school district spokesperson did not immediately answer if Waymo had complied with the request.

The letter prompted NHTSA to ask Waymo on November 24 if it would comply with the request to cease self-driving operations during student pick-up and drop-off times, adding: "Was an appropriate software fix implemented or developed to mitigate this concern? And if so, does Waymo plan to file a recall for the fix?"

NHTSA said in a letter to Waymo on Wednesday that it was demanding answers to a series of questions by January 20 about incidents involving school buses and details of software updates to address safety concerns.

(Reporting by David Shepardson)