A woman walking in Nob Hill was left with critical injuries Sunday, after a driver struck her as she crossed the street.

The collision, police say, occurred at 5:51 p.m. Sunday, at the intersection of Pacific Avenue and Leavenworth Street.

According to the San Francisco Police Department, the 91-year-old female victim was walking in the crosswalk at the intersection, which is governed by stop signs in all directions. A look at the intersection via Google Maps does not show a painted crosswalk at the intersection, but as noted by Walk San Francisco, "In San Francisco, all intersections of streets wider than 25 feet are legal crosswalks, unless they specifically say 'no crossing,'" likely explaining the use of that term in this case.

The 30-year-old male driver of a 2012 Mitsubishi Eclipse who was headed west on Pacific struck the woman as she crossed, police say, leaving her with serious head trauma.

The victim was transported to San Francisco General Hospital with life-threatening injuries, police say. An update on her condition was not available at publication time.

The driver remained on the scene, and was not arrested at the time of the collision, police say. As of Wednesday morning, police had not released additional information on any charges or citations the driver might have received as a result of the crash.

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