An Atherton man in his 60s was in serious but stable condition Thursday after his SUV apparently drifted onto a sidewalk off Middlefield Road in Palo Alto, struck a concrete planter and flew into the air, hitting a tree.

According to the initial police investigation, the car was traveling northbound on Middlefield, approaching the intersection with Hamilton Avenue, shortly after 8 p.m. Thursday, May 24.

No other vehicles were involved, and no other people were injured, Palo Alto police said. The man sustained moderate injuries, and Palo Alto Fire Department paramedics transported him to a local hospital.

The driver may have experienced a medical emergency that led to the accident, police said. Alcohol or drugs did not appear to be a factor.

Officers from the Police Department's Specialized Traffic Accident Reconstruction (STAR) team are investigating the crash. Police are asking any witnesses to call the department's 24-hour dispatch center at 650-329-2413.

— Palo Alto Weekly staff

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