The National Weather Service says a tornado that struck a workers' camp in the heart of North Dakota's booming oil patch last night was an EF-2 with winds peaking at 120 mph.
The weather service says a second brief tornado possibly occurred in the area based on eyewitness accounts.
Nine people at the camp were injured, including a 15-year-old girl who remains hospitalized in an intensive-care unit with a head injury. The girl was visiting an aunt and uncle at the camp.
The twister damaged or destroyed 15 trailers at the camp just south of Watford City.
North Dakota's oil boom has brought thousands of people to the area looking for work. Many live in hastily assembled trailer parks, known as man camps, with prefabricated structures that resemble military barracks.
APPHOTO NY108: This photo taken on Monday, May 26, 2014 and provided by Jill Helmuth, shows a tornado touching down on a reach before heading towards Watford City, N.D. Authorities say several were injured and more than a dozen trailers were damaged or destroyed Monday evening when the twister tore through a camp where oil field workers stay. (AP Photo/Jill Helmuth) (26 May 2014)
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APPHOTO CER603: This Monday, May 26, 2014 photo from video provided by Dan Yorgason, shows a tornado in a worker's camp near Watford City, N.D., in the heart of the state's booming oil patch. The tornado injured nine people, including a 15-year-old girl who suffered critical injuries, and damaged or destroyed more than a dozen trailers at the camp. (AP Photo/Dan Yorgason) (27 May 2014)
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APPHOTO RPJW204: Debris from a destroyed trailer is scattered Tuesday morning, May 27, 2014, after a tornado in Watford City, N.D. Authorities say at least eight trailers were destroyed Monday evening when the twister tore through a camp where oil field workers stay. Nine people were injured, including a 15-year-old girl critically. (AP Photo/Josh Wood) (27 May 2014)
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