Rafter, 11, missing in Arkansas River in Chaffee County

Crews are searching for an 11-year-old boy missing after falling out of a raft on the Arkansas River.

Chaffee County Sheriff John Spezze says the boy was on a guided rafting trip Wednesday afternoon when the raft he and two other people were in tipped on its side, knocking all three into the swollen river. The others were rescued from the river about 10 miles north of Salida, Colorado.

Searchers looked for the boy, who is from Golden, Colorado, until nightfall and resumed the search Thursday morning in Browns Canyon, a stretch of river known for its whitewater rafting.

The boy fell off in Big Drop Rapids, which are ranked as intermediate level rapids. The muddy river is running high because of melting mountain snow and recent rain.