A Santa Rosa man is in critical condition after a woman driving an SUV ran a red light and struck him while he walked in the crosswalk on Thursday afternoon, police said.

Santa Rosa police said Sherry Ann Gray, 80, of Santa Rosa, told investigators she was unaware she drove her Infinity FX35 through a red light and struck the man at the intersection crosswalk of Highway 12 and Middle Rincon Road before continuing to travel eastbound on Highway 12, where she subsequently rear-ended a Toyota RAV4 around 6 p.m.

The pedestrian, identified as Austin Polen, 25, was found unresponsive by paramedics and police just east of the crosswalk. He sustained major head trauma and had multiple broken bones, police said.

He was in critical condition on Thursday night.

Police said they received multiple 911 calls about the involved driver fleeing the scene after striking the pedestrian.

When Santa Rosa police officials began an investigation of the pedestrian being struck, they received a report that an SUV matching the one that witnesses described as fleeing the scene had rear-ended a RAV4 less than a mile up the road. The RAV4 was stopped at a red light at Highway 12 and Calistoga Road when it was struck by Gray, who stopped at that scene, officials said.

Police responded to the second location and determined that Gray was involved in both incidents. The driver behind the wheel of the RAV4 was not injured.

“Gray cooperated with investigators at the scene,” police said in a statement. “It did not appear that Gray was aware that she struck the pedestrian.”

Investigators do not believe drugs or alcohol were factors in the incidents.

It is unclear whether Gray will face any charges. Police did not immediately release additional information.

Gray hung up on The Chronicle when reached for comment Thursday.

Anyone with information about the incidents can contact Santa Rosa police Officer Jeff Adams at 707- 543-3636.

The intersection of Highway 12 and Middle Rincon Road was closed to eastbound traffic for several hours.

Lauren Hernandez is a San Francisco Chronicle staff writer. Email: lauren.hernandez@sfchronicle.com Twitter: @LaurenPorFavor