WISCONSIN DELLS, Wis. (AP) — Authorities in Columbia County are using sonar to try to find the body of a 21-year-old Chicago man who disappeared in the Wisconsin River near Wisconsin Dells.

Authorities say the man went under water at about 7:15 p.m. Saturday while swimming to shore. He did not resurface.

Divers from the Columbia County Sheriff’s Office worked until midnight to find the man. Search efforts resumed Sunday morning.

The incident happened in the Lower Dells, a few hundred yards south of the dam. Authorities say the man was fishing on a rock island area and appeared to get caught in a current as he was swimming back to shore. Family members and witnesses tried to rescue him but couldn’t.

The victim’s name is not being released at this time.

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