PHOENIX — Authorities say a driver was killed when struck by a hit-and-run vehicle on a Phoenix freeway.

Spokesman Raul Garcia of the state Department of Public Safety says the man was killed early Monday morning after his silver SUV broke down on northbound Interstate just north of Thomas Road and after a good Samaritan stopped to help.

The hit-and-run vehicle is described as a white or light-colored Chevy pickup with a short bed and custom taillights in the center of the rear bumper or tailgate. It got off I-17 at Bethany Home Road.

Garcia says the victim was struck after he got out of his vehicle, which was partially blocking the right-hand traffic lane.

The DPS initially said the victim was the good Samaritan.