Canadian officials have opened a criminal investigation into the deadly train fire and derailment that left at least 50 people dead or missing.<br/> <br />Police say some of the evidence recovered from the scene may indicate criminal negligence.<br/> <br />Late last Friday night, a fire started onboard a train hauling 72 cars of crude oil.<br/> <br />Later the train's brakes lost pressure and the train began to slide downhill. It went off the tracks and barreled into the town of Lac-Megnatic exploding into a fireball and incinerating nearby buildings.<br/> <br />Half of nearly 2,000 people evacuated have been allowed to return to their homes.<br/> <br />Police say they do not believe the incident was an act of terrorism.
