Emergency crews were called to the lake in Mapleton Township just before 12:30 p.m.
OPP said a family was in a boat and a man went into the water after a child who either fell or jumped into the lake.
The child was wearing a life-jacket but OPP said it doesn’t appear the man was wearing one.
Bystanders nearby were able to safely pull the child from the water but the man failed to resurface.
After several hours of searching the lake, OPP’s underwater search and recovery unit was able to find and pull the man’s body from the water just before 9 p.m.
He has been identified as Matthew Ottens of Mapleton Township. OPP did not confirm the relationship between Ottens and the child.
An autopsy is scheduled to take place on Monday.
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