At least one car of the 113-car train was carrying the chemical dimethylamine anhydrous, similar to anhydrous ammonia, which exploded and caused several train cars to catch fire.
After the explosion, the train's brakes automatically locked causing the derailment.
Area firefighters responded to the blaze and let the fire burn out.
No injuries were reported.
The Heartland Flyer, a train from Oklahoma City to Fort Worth, Texas, also travels on the tracks. Passengers were being bused to their destinations.
Residents within 1.5 miles of the derailment were evacuated from their homes, but were able to return to their homes by about 6:30 a.m.
Information from: The Daily Ardmoreite
Related:
Cause Of Oklahoma Train Derailment Still Under Investigation