CN Rail spokesman Jim Feeny said the 122-car train jumped the tracks shortly after 7 p.m. a few miles outside Plaster Rock, New Brunswick. The train was heading to Moncton from central Canada, the Canadian Broadcasting Corp. reported.
"The number of derailed cars has not yet been confirmed," Feeny said. "We do know that there are dangerous goods cars on the train and that they are in the derailment area these include cars carrying LPG -- which is propane -- and crude oil but we cannot confirm if those cars are actually derailed at this point. We know they're in the immediate area."
He said it was unclear what was fueling the fire.
Cpl. Marty Van Dijk of the Royal Canadian Mounted Police said emergency crews were working with the train's conductor to determine what was in the burning cars.
"Our emergency responders are just beginning to arrive, the local fire department is also on site," he said.
Feeny said the cause of the derailment was unknown. No crew members were hurt, he said.
Van Dijk said a hazardous materials team was on its way to the accident scene and people within 1 1/4 miles were being evacuated.
Witness J.D. Saddler said he saw "a great big cloud of orange smoke and the flames were really high in the air."