A 22-year-old woman was hospitalized with critical injuries Tuesday, after a driver struck her as she ran across a Civic Center-area crosswalk.

According to the San Francisco Police Department, the woman was running west on McAllister Street when she stepped into the crosswalk at Hyde Street at 3:58 p.m. Tuesday.

A 22-year-old male driver who was headed south on Hyde struck her as she ran across, causing a "head injury and spinal fracture" that police consider life threatening.

The driver remained on the scene and cooperated with police. He was not arrested, according to the SFPD.

The runner was transported to San Francisco General Hospital, where she remains this morning. Neither an update on her condition nor additional details on the collision were available at publication time.