UPDATED 06/29/12 10:02 a.m.

ANTIOCH, Ill. (CBS) — The search has resumed for a 62-year-old man who jumped off a boat for a swim in a lake in Antioch and couldn’t get back onboard, although the man is now presumed dead.

About 40 divers from fire departments throughout Lake County searched for the missing man’s body until about 8 p.m. Thursday. On Friday, about eight divers were in the water along with sonar.

LISTEN: WBBM Newsradio’s Bernie Tafoya reports

As WBBM Newsradio’s Bob Roberts reports, the man was on a pontoon boat with another man, 69, in West Loon Lake near Illinois Route 83 and Grass Lake Road, when the younger man decided to hop off the boat and go for a swim about 2:15 p.m. Thursday, Lake County Sheriff’s police Lt. Karen Kates said.

But the 62-year-old man had trouble climbing the board. The older man jumped into the water to rescue the younger man, but

The 62-year-old man was unable to get back onto the boat and the older man jumped into the water to help him, but neither man was able to get back on the boat, Kates said.

One of the men called for help, and a passing boater was able to save the 69-year-old man, Kates said. But the younger man disappeared.

The search for the man continued as of late Friday morning.

The Sun-Times Media Wire contributed to this report.

(Source: Sun-Times Media Wire © Chicago Sun-Times 2012. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed.)

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