NORTHGLENN, Colo. (AP) — Police in Northglenn are trying to determine how a man was injured in a fire while sitting on his tractor.The police department said in an email that authorities were called to a parking lot on Thursday after a witness saw the man and rushed to his aid.The witness grabbed a fire extinguisher from his truck and smothered the flames.The unidentified man was taken to a hospital, where the extent of his injuries was not available.Read more on Colorado Springs Gazette