EL DORADO COUNTY (CBS13) — Authorities say a search is on for three young men from Sacramento who were last seen being swept into the Cosumnes River.

The men were last seen on Thursday afternoon in the North Fork of the Cosumnes River at the Happy Valley Cut Off, the El Dorado County Sheriff’s Office says.

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Exactly what led up to the men being swept into the water is unclear.

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Deputies, a dive team, a helicopter and multiple fire and rescue crews responded and searched for the men but came up empty on Thursday.

Dive team units are were back out on the water Friday morning continuing their search for the men.

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The names of the men have not been released at this point, but deputies say they are two 20-year-olds and a 24-year-old. All three are residents of Sacramento.