(CNN) -- A train carrying crude oil derailed Monday in West Virginia and exploded, filling the sky with thick clouds of fire and smoke.
One home was destroyed, but there were no reports of injures, according to Lawrence Messina, spokesman for the West Virginia Department of Military Affairs and Public Safety.
Nearly 30 of the train's more than 100 cars came off the tracks, he said. It's unclear what caused the derailment, which happened around 1:30 p.m. in Fayette County, West Virginia.
Oil from the train spilled into the Kanawha River, a source of drinking water in Kanawha and Fayette counties. Gov. Earl Ray Tomblin issued a state of emergency for both those counties Monday night. Area residents are being urged to conserve water.
Police are also asking residents within a half a mile of the scene to evacuate until further notice.
Messina said authorities are still gathering their facts.
"We've had some severe winter weather conditions here with significant snowfall. We don't yet know whether that's a factor in this," he said.
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