Richard Manning, the 62-year-old man accused of killing Norman Gallman in the midst of a road rage dispute Tuesday, is a former Hamilton County sheriff's officer, an instructor of armed guards at a Chattanooga shooting range and a cancer patient.

Manning is accused of firing one fatal shot at Gallman on Tuesday morning at the Moore Road and North Terrace intersection near East Ridge after he pulled up behind Gallman at a stoplight.

According to police, another motorist saw the driver of a bronze Chevrolet Impala pull up directly behind Gallman at a stop light. The witness told police that Gallman got out of his Honda CR-V and walked back to the Impala's driver-side door. A shot was fired.

Gallman reportedly stumbled back to his SUV and "slumped over the steering wheel." A woman in the car was uninjured.

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