The driver apparently fled the scene, but was later detained and questioned. Police found the green San Francisco Recreation and Parks' vehicle not too far from Holly Park in the city's Bernal Heights neighborhood.
Authorities say the woman and her daughter were under some trees when the vehicle struck her shortly after 2 p.m. on Thursday.
Fire department spokeswoman Mindy Talmadge says the woman was taken to San Francisco General Hospital where she was pronounced dead from her injuries.
The name of the woman hasn't been released. Her daughter was unharmed.
Police spokeswoman Tracy Turner says the department's hit-and-run unit is investigating the incident.
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