A pedestrian advocacy group is renewing the call for safer streets after a weekend crash in San Francisco’s West Portal neighborhood left three people dead, two injured, and sent an elderly driver to jail on potential felony charges.

Mary Fong Lau, 78, was booked Sunday on suspicion of felony vehicular manslaughter, felony reckless driving causing bodily injury, and additional traffic violations that include driving at an unsafe speed, San Francisco police said.

Fong Lau was driving a white SUV and headed east on Ulloa Street about 12:13 p.m. Saturday when she allegedly crashed into a San Francisco Muni bus stop at Ulloa and Lenox Way, police said.

Two people in the bus shelter died at the scene and three others, including the driver, were hospitalized.

A woman who was one the hospitalized patients later died, and an infant was still suffering from life-threatening injuries, police said Monday.

“This incident was a heartbreaking tragedy. The San Francisco Police Department offers its deepest condolences to the victims, their families and loved ones, and everyone at the scene who witnessed and assisted first responders,” the police department said in a news release.

“I’ve just visited the scene and it is heartbreaking,” San Francisco Mayor London Breed said in a post at 3:54 p.m. Saturday on X, formerly known as Twitter. “We will share more information when we can, but now our focus is on the victims and their families.”

Walk San Francisco, a pedestrian advocacy nonprofit, identified those killed on Saturday as a man and a toddler.

“This is one of the worst pedestrian tragedies to ever occur on San Francisco streets,” Jodie Medeiros, executive director of the organization, said in a statement.

Walk San Francisco organized a vigil for the victims at the crash site Monday evening, she said.

West Portal Avenue is a major commercial corridor with significant foot traffic and the K and M Muni rail lines running on the surface, according to Walk San Francisco.

“It’s time to fundamentally rethink areas like where this crash occurred, where thousands of people walk and cross and wait every day,” Medeiros said.

“It’s time to fundamentally rethink areas like where this crash occurred, where thousands of people walk and cross and wait every day.” Jodie Medeiros, Walk San Francisco

A petition launched on the Action Network website by Luke Bornheimer, an advocate for sustainable transportation policy and infrastructure, took the call for improved pedestrian safety one step further, asking readers to join a letter-writing campaign urging Muni to close the intersection of West Portal and Ulloa Street.

“Closing this intersection to cars will instantly make it safer for people, including people who need to drive or use cars, in addition to improving the speed and reliability of public transportation to and from West Portal,” the petition reads in part. It had received 1,770 signatures as of Monday evening.

San Francisco police said an investigating into Saturday’s crash is on-going, but they do not believe that traffic engineering was a factor in the collision.

The victims of Saturday’s crash were the city’s fifth and sixth pedestrian deaths this year, Walk San Francisco said. Sunday’s death brings that number to seven.

That figure is more than double what it was at the same time last year, according to pedestrian advocates. In 2023, 17 people were killed while walking in San Francisco, the organization said.