WELD COUNTY, Colo. (CBS4) – Investigators in Weld County are looking for a red truck because the driver may have witnessed a deadly road rage crash.

Esteban Moreno Jr., 39, was killed in the crash last week on Highway 85.

(credit: CBS)

(credit: CBS)

(credit: CBS)

(credit: CBS)

Police arrested Blair Jackson, 48, on charges of second-degree homicide and reckless driving. Jackson is a police officer from the town of Ault. He was off duty at the time of the crash.

Jackson is on unpaid leave from the Ault Police Department during the investigation.