A man was left with life-threatening injuries on a busy SF street Thursday, after an incident police characterize as a traffic collision between a vehicle and a pedestrian.

According to the San Francisco Police Department, the crash occurred at 7:12 a.m. Thursday, near the intersection of California Street and Van Ness Avenue.

In a written report, the SFPD says that the victim, who they describe as between 30 and 40 years of age, was transported to an area hospital with life-threatening injuries as a result of the wreck.

Police say that a witness to the incident "saw the vehicle rolling and heard [the victim] screaming." The victim, police say, "was pinned under the vehicle."

The driver of the vehicle was described by police as "unknown." And unknown is also an apt description for any other information in the case — What were the circumstances of the crash? Was this a parked vehicle, perhaps? Or if both parties were in motion, did the driver remain at the scene? — as a Friday morning call to SFPD with follow-up questions was not returned as of publication time. Needless to say, when they do call back, this report will be updated.

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