A San Francisco train operator is under scrutiny after allegedly falling asleep at the controls while on duty, leading to a jarring collision between two out-of-service trains.

Dramatic footage shows the operator appearing to nod off moments before the empty train crashes into another rail vehicle, smashing both windshields on impact. The force of the collision immediately wakes the operator.

The video was first obtained by NorCal Bodycam.

The crash happened on the morning of July 31 near 47th Avenue and Wawona Street, just north of the San Francisco Zoo. According to officials, both trains were not in service and were laying over between scheduled runs, meaning no passengers were on board when they collided.

The San Francisco Municipal Transportation Agency has launched an investigation into the incident, which remains ongoing.

“This type of incident is simply unacceptable. While the formal investigation of the collision is ongoing, vehicle and infrastructure issues have been ruled out, and the initial determination for the incident is operator error caused by fatigue,” the SFMTA said in a statement, according to ABC News.

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The episode has renewed concerns about operator fatigue in San Francisco’s transit system, as it is not the first time a local train operator has appeared to fall asleep while behind the controls.

In a separate incident, video showed a female operator slumped in her chair as a crowded train took a turn sharply and accelerated out of a curve.

The fast turn threw riders to the side, with many flung to the floor. “I wanna get off!” one terrified woman wailed in the video, while another yelled, “Oh my God!”

The jolt also woke the driver, who was seen rushing to get control and bring the train to a halt. She then addressed the terrified passengers, repeatedly telling them to “relax.”

The transport agency formally determined operator fatigue was the primary cause of that collision.

In response to these findings, the SFMTA launched a systemwide fatigue-awareness education campaign. The program was designed to train transit operators on recognizing early signs of exhaustion, managing sleep schedules, and preventing similar human-error incidents across the city’s rail network.