SAN DIEGO >> A driver plowed through a crowd on a sidewalk under an overpass with homeless tents on a rainy morning today in downtown San Diego, killing three people and injuring six others, including two who are hospitalized in critical condition, police said.

The driver — whom authorities identified only as a 71-year-old man — appeared to lose control of his Volvo station wagon shortly after 9 a.m. near a community college, said San Diego Police Chief David Nisleit. He was arrested on suspicion of driving while impaired.

“For whatever reason, (the driver) veered to the right, went up on the sidewalk, struck multiple pedestrians there and then came back on to the roadway,” Nisleit said

Three people died at the scene. Five of the six others who were injured were taken to hospitals, authorities said.

Nisleit offered “my deepest condolences,” to the families of those who died.

The sidewalk had tents on it. Nisleit said homeless people may have moved under the bridge to get out of the rain just before the car plowed through there.

“I don’t know if people were sleeping or people were sitting there,” he said, adding that authorities scrambling to get people medical help would then turn to finding the answers to those questions.

The driver got out of his car and tried to help people before identifying himself to police, Nisleit said.

“He was cooperative, (and) did not try to run away,” the chief said, correcting earlier reports from police that he had tried to flee.

Multiple ambulances, five fire engines, a helicopter and more than 60 first-responders rushed to the scene near San Diego City College where on a typical weekday morning it is a busy area with students walking by.

“Our crews found, obviously, a tragic incident under the bridge,” San Diego Fire Department Chief Colin Stowell said.