A small town in North Dakota is being evacuated tonight after a 100-plus-car freight train carrying crude oil derailed this afternoon, causing explosions that sent 100-foot-high flames into the sky:

No deaths have been reported, but residents of Casselton, less than a mile away from the derailment, were urged to evacuate when the wind shifted, sending oily smoke in their direction.

Here's a map of the area that shows just how close the derailed train was to the town. Also note that trains pass through the area so frequently that one happened to be driving through when the satellite was passing over:

It's not entirely clear yet how the derailment occurred. According to the AP, Burlington Northern Santa Fe, which owns the train, said another train derailed and the oil train crashed into it. Authorities, however, "hadn't yet been able to untangle exactly how the derailment happened." Time is reporting that it was the oil train that went off the tracks first, then it was hit by a second train.

However it happened, at least 10 cars are on fire now, Reuters reports, but it's very possible the fire could spread to more as not all the cars have been cleared from the scene yet. Fire crews won't be able to start fighting the fire until it dies down somewhat, probably tomorrow morning, according to Valley News Live's Matt Moore, who also reported that one of the trains' conductors suffered second degree burns. (BNSF says no one was hurt.)

Only a few hours before the crash, BNSF's executive chairman Matthew Rose was telling the Dallas Business Journal that the company was expecting to increase the amount of crude oil it hauled by 33 percent over the next year, from 750,000 barrels to 1 million. Rose was very excited about this:

'This oil is replacing that previously imported oil, and I think that’s great news for our country,' Rose said. 'The East Coast refineries would have been taking in imported oil, so the Bakken will be substituting for that.'

"The Bakken" is the name for oil that comes from the Bakken Formation, a.k.a. "ground zero in America's energy renaissance," as Fox News wrote on Christmas Eve. The crude oil from Bakken is believed to be lighter and more volatile than normal crude, prompting the Bismarck Tribune on December 26 to call for a review of how Bakken oil was transported, in the hopes of avoiding a derailment disaster like what happened in Lac Megantic, Canada in July. Forty-seven people were killed when a train carrying Bakken oil derailed. Last month, another train carrying Bakken oil derailed in Alabama, resulting in 300-foot-high flames. No one was injured in that crash.

And on December 19, the AP's Matthew Brown and Josh Funk wrote a long article detailing the safety concerns many towns had as the number of oil trains passing through them exponentially increased in the last few years. While large cities may have more resources and personnel on hand to deal with a derailment, rural areas may only have a volunteer fire department and little if any of the foam needed to control oil fires on hand. That said, the article also noted that BNSF had its own hazardous materials emergency crews spread across the country and one official praised the company as being "Johnny on the spot."

Rail companies haven't been quite so "Johnny on the spot" when it comes to retrofitting their rail cars to make them safer. Reuters noted after the Alabama derailment that the National Transportation Safety Board recommended that tank cars be reinforced. But at the cost of over $1 billion for the estimated 300,000 cars, rail companies have been reluctant to do so.

A week ago, Bismarck Tribune's Lauren Donovan wrote about the region's worries when it came to derailments and oil fires:

Beach Fire Chief Dan Buchholz says unit trains loaded with Bakken crude pass through the heart of his community every day and a derailment is a catastrophe to contemplate.

“I mean right through the middle of town. It would affect them directly,” Buchholz said.

The possibility is a real concern. Two shipments of Bakken crude have derailed in the past half year. Both resulted in explosive fires.

The North Dakota Firefighter's Association, Donovan noted, was sponsoring crude oil fire training using rail cars -- but that doesn't start until next fall, and it won't offer specialized training for Bakken crude.