RAPID CITY, S.D. (AP) - Four people have died in a fire in Rapid City. Three of the victims were children.

The blaze in what authorities described as a multi-family structure in the west side of the city was reported shortly before 11 p.m. Tuesday. An adult was pronounced dead at the scene, and the three children were pronounced dead at a local hospital.

Lt. Brent Long of the Rapid City Fire Department says the cause of the fire is under investigation. He says officials cannot immediately release the names and ages of the victims, but more information is expected to be released later Wednesday.

Long says such a fire is unusual in South Dakota.

The American Red Cross helped 17 displaced people find a place to stay for the night.

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