The CHP is continuing its investigation into a driver who ran over a woman lying in a Santa Rosa Avenue crosswalk.

Melissa Tucker, 29, remained at Stanford Medical Center, according to the CHP. She was flown there Sunday after suffering severe injuries.

CHP officers reviewed surveillance tape taken from a nearby business but found nothing to shed light on what happened, CHP Officer Kerri Post said Tuesday.

Driver Irvin Sandoval, 24, of Santa Rosa and his wife were headed down the avenue for church at about 7:10 a.m. in a Honda Accord.

It wasn't yet light and Sandoval reported he could see something on the ground ahead but by the time he realized it was a person he couldn't avoid hitting her.

Sandoval, an ambulance EMT, stopped and tried to help the woman.

Why Tucker was on the ground -- whether she'd collapsed or had been hit by a car previously -- remained unknown Tuesday. Officers had not yet attempted to interview Tucker, Post said.

The incident occurred at Santa Rosa and East Robles avenues, just south of Santa Rosa.

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