OSWEGO, Ind. (WOWO): It’s been nearly one week since a man went underwater and never resurfaced on Tippecanoe Lake.

Last Friday, July 8, 70-year-old John J. Forbes Sr. of Chicago was with his wife, son and a family friend when he went swimming off a boat and went under.

Officers are continuing to utilize side scan sonar to image the bottom of the lake, according to a press release from the Indiana Department of Natural Resources. They believed his body could be in depths greater than 100 feet.

Forbes was not wearing a life jacket at the time of his disappearance.

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