A 21-year-old is presumed drowned after falling out of a boat on Rock Lake, about 40 km east of Killarney Friday evening.
Three Winkler males were fishing when one fell into the water and did not resurface.
"The others got into the water to try to assist," said RCMP spokesperson Tara Seel.
Killarney RCMP responded to the report at 7 p.m. Friday and continue to investigate with the help of the RCMP Underwater Recovery Team.
No one in the boat of the occupants of the boat were wearing life jackets.
The name of the male will not be released.