A shooting at the peak of rush hour Wednesday night stopped traffic in a busy area of downtown San Francisco.

Police say that it was 5 p.m. when officers heard gunfire on the first block of Mason Street, which is between Market and Eddy Streets.

According to the San Francisco Police Department report on the incident, responding officers discovered a 25-year-old man at the scene, suffering from gunshot wounds.

SF Weekly reports that the incident involved a gunman on a bike and the driver of an Uber.

According to the Weekly, witnesses say a man on a bike was arguing with the driver of a black Nissan sedan with an Uber sticker on its window, then shot him.

“The guy on a bike shot someone in the car,” a witness tells SF Weekly, which noted that the Uber vehicle "sat parked by the curb, the driver’s side door open, and a bullet hole visible under the rear passenger-side window."

(In an email to SFist, SF Weekly's Nuala Sawyer, who reported on the case, acknowledges that the witness statements contradict one another slightly, as one mentions a shooting following an argument and another says it was a confrontation between a man on a bike and someone in an Uber. While reporting from the scene, Sawyer says officers wouldn't answer her questions on the circumstances of the shooting, "so I included both perspectives." Sawyer's request for more information from SFPD has yet to be responded to, she says.)

The injured man was transported to an area hospital with life-threatening injuries, police say.

The SFPD says that the suspect, a 26-year-old man, was caught near the scene. He was "arrested and handgun located," according to the police report.

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