Video footage broadcast this morning shows a chilling scene on a San Francisco freeway, when a group of motorcyclists appear to beat up a motorist trapped in their illicit sideshow Wednesday night.

Sent to KRON 4 by an unnamed source, the video takes place on southbound 101 near Hospital Curve (aka the Cesar Chavez exit). A group of motorcyclists, many of whom are not wearing helmets, reportedly "took over" the freeway and were performing tricks and "popping wheelies." According to KRON 4's source, the group is "a known local bike gang."

At some point during the unpermitted event, "there appears to be a little bump" between the driver and the side show participants, KRON reports. Another driver, who appears to be with the motorcyclists, pulls in front of the Corolla and boxes it in as the bikers surround the vehicle.

When the Corolla driver got out of his car, possibly, KRON says, "to defuse the situation," he was beaten severely, and suffered injuries including a broken leg. He remains hospitalized as of Thursday morning.

When officers with the California Highway Patrol responded to the scene, the sideshow participants, who included dirt bike riders and an all terrain vehicle, had fled the scene. When showed the video by KRON 4, a CHP spokesperson said that they might be able to track at least one of the participants down using license plates visible in the footage.

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