Police say they are seeking a San Francisco driver on suspicion of assault with a deadly weapon, after the suspect struck a pedestrian as he walked on a SoMa street.

According to the San Francisco Police Department, the incident occurred at 2:39 p.m. Thursday, at the intersection of Folsom Street and Harriet Street, a short alley that runs parallel to Sixth Street.

Police say that the victim, a 21-year-old man, "was walking in the middle of street" when he "heard a car engine revving."

The next thing he knew, he was struck by a vehicle, police say.

The driver fled the scene, and the victim was transported to an area hospital with injuries police say are life-threatening. The driver remains at large as of Friday, and police say that no arrests have been made in the case.

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