By CBS13 Staff

COLUSA COUNTY (CBS13) – A search is continuing in the Sacramento River near the community of Colusa after a possible drowning over the weekend.

The Colusa County Sheriff’s Office says, Sunday evening, they got a report about someone going under the water just east of Levee Park.

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Witnesses reported seeing the person, who wasn’t wearing a life vest, struggling while trying to swim across the river.

A search of the river was done by the Colusa County Sheriff’s Office boating safety unit Sunday night, but no victim was found. Search efforts resumed the next day, but so far have come up empty.

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Authorities say a cadaver K9 unit and an underwater robot have been used in the search.

The search effort will be continuing through the week, the sheriff’s office says.

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Colusa County authorities say the possible drowning victim is a 19-year-old man from Arizona. His name has not been released.