WATFORD CITY, N.D. (AP) — A tornado that struck a North Dakota oil worker camp has injured nine people, one of them critically.

An emergency management official in McKenzie County says the tornado that struck the camp about 5 miles south of Watford City Monday destroyed eight trailers where workers lived.

He says rescue crews are searching a large amount of debris, but he's confident no one is missing. He says the camp where the tornado hit had quite a few more trailers just a few days ago, so the casualties could have been higher had it happened earlier.

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