Railroad company BNSF said it had received a report of a freight train derailment near the storm-hit city of Bay in Arkansas, without specifying the cause.
Late Wednesday, Arkansas, Kentucky and Tennessee declared a state of emergency.
The National Weather Service said parts of Arkansas, Missouri, Indiana, Illinois, Ohio and Texas were under a high risk of severe thunderstorms on Thursday, warning of more tornadoes, hail and life-threatening flooding.
"The word for tonight is 'chaotic,'" Scott Kleebauer, a NWS meteorologist, said on Wednesday. "This is a large expanse of storms migrating slowly to the east, stretching from southeast Michigan down into southeastern Arkansas."
REUTERS - WEATHER-OKLAHOMA-STORM2- APRIL3
Missouri's Emergency Management Agency said a tornado that hit the town of Nevada, Missouri had caused "major damage to several businesses, power poles were snapped and several (empty) train cars were flipped onto their sides..."
More than 400,000 customers had their power knocked out across the storm-hit area, according to PowerOutage.us.
(Reporting by Brad Brooks in Colorado, Surbhi Misra and Gursimran Kaur Mehar in Bengaluru; additional reporting by Devika Nair; editing by Peter Graff and Mark Heinrich)
Thumbnail image courtesy: Cherokee Nation Marshal Service/Handout via REUTERS/File Photo
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