The driver who allegedly struck three pedestrians and a Muni bus in the Mission District on Wednesday has been taken into custody, police said.
Stephan Kernan, 62, was arrested in connection with the collision that seriously injured two people near 23rd and Mission streets around 4:20 p.m.
Kernan was booked on suspicion of hit-and-run driving resulting in injury and failing to stop for a red light, according to police.
Police initially suspected that the driver was impaired but, as of Thursday morning, had ruled out drugs or alcohol as a factor in the incident.
Kernan was allegedly driving north on Mission Street in a Prius when he struck the two pedestrians.
The driver then struck the bus and a person exiting the bus before leaving the scene.
Police say Kernan and a passenger in his vehicle were detained after returning to the scene.
The victims are a 49-year-old man, a 33-year-old man and a 69-year-old woman, police said.
Two remained in life-threatening condition on Thursday morning. The third, the bus passenger, is expected to survive after being treated at the scene.