A CN freight train carrying crude oil derailed early Saturday in northern Ontario, causing at least 10 cars to jump the tracks.

Ontario Provincial Police said the derailment happened near Gogama, Ont., around 2:45 a.m. Saturday morning, with some of the cars catching fire and others falling into the Mattagami River.

A CN spokesperson said that an initial assessment indicated that five tank cars landed in the waterway and that a bridge had been damaged by the derailment. Some of the tanks were still on fire early Saturday evening. Emergency crews were still trying to determine the exact number of cars that derailed.

Residents of Gogama and the local Mattagami First Nation have been instructed to stay indoors until further notice to prevent possible smoke inhalation. They have also been told to avoid drinking water from the "community source," police said.

OPP Const. Gillian Coughlin told The Canadian Press that officers are on scene, and firefighters from the nearby Gogama Fire Department have been called in help douse the flames. Gogama is about 80 kilometres south of Timmins, Ont.

"There has been nobody injured which is crucial, but we definitely do have an issue going on there with cars that caught fire," Coughlin added.

The Gogama Fire Department released a statement saying the smoke itself is not toxic, but particles in the smoke may be dangerous. The department recommended anybody with breathing disorders stay inside until further notice.

"Emergency crews are conducting a full site assessment and activating the emergency response plan with local officials," CN spokesperson Emily Hamer told The Canadian Press.

A local business owner told The Canadian Press the fire spread quickly along the Mattagami River and destroyed a bridge on the outskirts of Gogoma.

"We have two exits in Gogama to get in and out of town and the bridge apparently is burned down," said Roxanne Veronneau, owner of the Gogoma Village Inn.

"So now we have one other exit, which is relatively close to where all of this is going on."

The derailment also closed a section of Highway 144, between Highway 560 and Mattagami Reserve Road. The road is a major route connecting Timmins with southern Ontario. It is expected to remain closed for 24 to 36 hours, the OPP said.

Via Rail passenger service has also been cancelled between Winnipeg and Toronto. You can check the status of Via trains here.

Veronneau says that people in Gogama are on "edge," and she feared that the derailment could be a repeat of the deadly rail disaster in Lac-Megantic, Que.

"They're not impressed because it could have happened right here," she said. "Look in Quebec what happened to them and how many lives were lost.

"My inn is about 200 feet from the train tracks and it's a major concern for the people in town ... If it had happened in the middle of town we wouldn't be having a conversation right now because we would have gotten taken out. It would have been horrible being this close and the track runs right through the middle of Gogama."

Coughlin says that the cause of the derailment is still being probed, and the Transportation Safety Board of Canada has deployed investigators to the site.

CN said the crude oil being transported originated in Alberta and was destined for Eastern Canada.

This is the third time in the past month that a CN train has gone off the tracks in northern Ontario.

On Feb. 14, 29 train cars derailed south of Timmins. In that incident, seven cars caught on fire, and Via Rail passenger trains were forced to cancel trips along the route from Winnipeg to Toronto.

Another CN freight train carrying crude oil or gasoline derailed Thursday about 100 kilometres east of Hornepayne, Ont., but there was no spillage in that incident.

CN said the train that derailed on Saturday was outfitted to meet new upgraded standards for cars carrying crude oil and other flammable liquids. The changes were instituted in light of the Lac-Megantic disaster two years ago, which resulted in 47 deaths.

However, after the incident in February, the agency said the upgraded cars still "performed similarly" to those in involved in Lac-Megantic, and that last month's incident "demonstrates the inadequacy" of the new standards.

CN is urging Transport Canada to institute even greater protection standards to reduce the risk of spills.

With files from The Canadian Press and CTV Northern Ontario