Kentucky State Police spokesman Jonathan Biven said none of the injuries sustained in Wednesday's accident were life-threatening, CNN reported.
The bus had left Cub Run Elementary School in Cub Run, Ky., when it went off the highway in Hart County as it was rounding a curve, flipping onto its side, state police said.
The trip to the nation's capital was not a school-sanctioned event, but was organized by parents and WorldStrides, a student travel company, Biven said.
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