The train which derailed during a snowstorm in West Virginia, sending a massive fireball into the sky, was carrying crude from the Bakken oilfields in North Dakota.
The derailment happened around 1:20 p.m. Eastern time on Monday, with up to 15 train cars coming off the tracks in Fayette County – some of which caught fire, prompting a huge explosion, the LA Times reports.
The newspaper notes the 109-car CSX train was carrying oil from the Bakken shale formation to Yorktown, Virginia, and that following the crash, one of the tankers is believed to be leaking oil into the Kanawha River.
Train operator CSX is primarily based in the eastern United States, only going as far west as St. Louis and Chicago, so it does not run routes through Minnesota, North Dakota or Wisconsin.
But each week around 50 oil trains carrying a million gallons of crude Bakken oil pass through Minnesota, from North Dakota or Alberta, on the way to refineries in southern and eastern United States, with the majority of these going through the Twin Cities.
Last month, state officials said first responders in Minnesota are "not prepared" to deal with an oil train disaster.
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The West Virginia incident is just the latest in a series of high-profile derailments involving oil trains.
A state of emergency has been declared in the area and 1,000 people have been evacuated. The Associated Press reports that the crash comes as transport officials weigh tougher safety regulations for oil transportation that would phase out "tens of thousands of older tank cars."
Reuters says the inability to replace aging tank cars is an "astonishing example of regulatory failure," given that they were recognized as necessary for public safety in 2012, and stricter rules governing them aren't likely to be rolled out until 2017-18.