A taxicab moving in reverse jumped a curb at a busy crosswalk near Union Station, striking a light pole and at least two pedestrians during the Thursday morning rush, authorities said.

The driver and one pedestrian were taken to the hospital in critical condition, while the other pedestrian was transported in serious condition, according to Chicago Fire Department spokesman Joe Roccasalva. A female passenger in the cab refused treatment at the scene.

The accident shortly before 8 a.m. happened when the taxi's driver put the cab in reverse and backed into the pedestrians on the sidewalk, said Chicago Police Sgt. Antoinette Ursitti.

Ursitti said none of the injuries appeared to be life threatening and the police investigation was continuing.

Schuyler Pepin, 14, said he was selling newspapers on the street nearby when he saw the taxi driver apparently arguing with a driver in another cab.

Pepin said the driver of the taxi that crashed appeared to be attempting to put his cab in park, and had the driver's side door open as if he were going to get out of the vehicle.

Pepin said it seemed that "he thought he put it in park, but he had it in reverse."

The cab then moved quickly in reverse over the curb and hit the pedestrians on the sidewalk, the teen said.

A woman who answered the phone at Chicago Carriage Cab, the company name on the cab towed from the scene, said the company had no comment.

The crosswalk where the crash occurred is just west of a bridge over the Chicago River and near an exit from Union Station, a busy Amtrak and commuter train station. The area was jammed with pedestrians during the morning rush hour at the time of the crash.