The crash happened around 10:25 a.m. in an area that's mostly warehouses. San Francisco police said the driver of the vehicle was involved in some type of physical altercation with a group and then struck five people before fleeing.
A witness at the scene said the driver first wielded an ax, swinging it at the group. The driver then got into a van, rammed the vehicle into the group and sped off. Police have not confirmed that witness account.
Four people were taken to a local hospital with life-threatening injuries. At least one of those victims died.
Authorities said they arrested a man named Mark Dennis in connection with the crash. He had a white GMC Safari van that was recovered at the scene with several "suspicious dents."
The incident was under investigation.