Video: At least one person dead and 80 missing after train carrying crude oil explodes in Quebec Michel Brunet, a spokesman for Quebec's provincial police, said late Saturday the official death toll remained at one but added: "We expect there will be more fatalities." Radio-Canada had earlier reported that 60 people were unaccounted for in Lac-Megantic, where the blaze was still raging, 20 hours on. "There have been several reports" from people who said they were unable to reach relatives who lived near the accident site, Brunet said. "The fire is still raging, our investigators have not yet even be able to get close to the scene," he added, more than 12 hours after the incident. An initial evacuation zone of a kilometre around the crash site was widened Saturday as a precaution against harmful particles in the air, bringing the total to 2,000 people forced to leave their homes. Around 150 firefighters were battling the blaze, including some who came across the border from Maine, just 25 kilometres south of the town. The cause of the crash was still unknown, but a spokesman for the Montreal Maine & Atlantic company, Christophe Journet, told AFP the train had been stopped in the neighbouring town of Nantes, around 13 kilometres west of Lac-Megantic, for a crew changeover. For an unknown reason, Journet said, the train "started to advance, to move down the slope leading to Lac-Megantic," even though the brakes were engaged. As a result, "there was no conductor on board" when the train crashed, he said. A team of investigators from Canada's transportation safety agency was quickly dispatched to the scene to investigate. One witness, Nancy Cameron, posted a photo on social media websites showing one of the train's locomotives spouting flames near Nantes. Other witnesses were in Lac-Megantic when the train came barrelling in. "When we came out of a bar, we saw cars arriving in the centre of town at full speed," Yvon Rosa told Radio-Canada. We heard explosions and there was fire everywhere. We ran to the edge of the water," Rosa said. Prime Minister Stephen Harper offered his "thoughts and prayers" to the community and said the federal government was ready to provide assistance. The Montreal Maine & Atlantic train consisted of five locomotives and 77 rail cars and was carrying oil from the US state of North Dakota, said the company's vice president of marketing, Joe McGonigle. But Quebec authorities spoke of 72 cars transporting 100 tonnes of oil each. "Around 10 cars have been secured and separated from the train," the Quebec emergency agency said in a statement. The Montreal Maine & Atlantic company has a network of more than 800 kilometres through Quebec and New Brunswick provinces and the neighbouring US states of Maine and Vermont.