Waymo said Saturday that it was stopping service across San Francisco after numerous online videos showed its autonomous vehicles snarling traffic during the citywide blackout.

“We have temporarily suspended our ride-hailing services given the broad power outage in San Francisco,” wrote Suzanne Philion, a company spokesperson, a little after 7 p.m. “We are focused on keeping our riders safe and ensuring emergency personnel have the clear access they need to do their work.”

About a third of San Francisco lost electricity throughout the day Saturday after rolling Pacific Gas & Electric Co. blackouts hit some 125,000 homes and businesses. It was not clear when the power would be restore, but the utility said it was “possible” it would happen later Saturday.

Traffic lights across the city were down, seemingly halting Waymos in their tracks. Riders and pedestrians posted videos of Waymos stuck at intersections with long lines of drivers behind them.

Many of the videos and images showed Waymos stuck one behind the other, with human drivers passing them by.

Groups of two, three, as many as five Waymos were stuck at different corners across the city, blinking red lights in the rain.