CATASAUQUA, Pa. (AP) - A man pronounced dead on railroad tracks under a bridge had jumped after running from a police officer who fired a stun gun at him, a prosecutor said Tuesday.

Authorities in Lehigh County said the body of Thomas Duffy, 62, of Whitehall Township, was found Monday under the span in Catasauqua.District Attorney James Martin said a Catasauqua officer tried to pull over an SUV after a traffic violation early Monday, but the vehicle refused to stop and made several turns before halting on the bridge. After the driver fled from the car on foot, the officer gave chase and ordered the man to stop, then fired a stun gun, which appeared to hit the subject in the back but had no apparent effect, Martin said."The subject then moved to the rail, threw his leg up onto and over the ledge of the bridge and rolled off of the bridge," Martin said in a statement. "He fell approximately 32 feet to the ground below the bridge in the area of the Norfolk Southern Railroad line."Duffy was pronounced dead at the scene. An autopsy determined that the stun gun probes had failed to penetrate Duffy's skin, and officials are awaiting the results of toxicology tests, Martin said.Dashboard camera video from the patrol vehicle appears to show that "Duffy went over the rail of the bridge completely voluntarily and without any action" on the part of the officer, Martin said.