Grey Bruce OPP continue to search for a swimmer who went missing in the water inside the Grotto at Bruce Peninsula National Park.
Police were called around 4:17 p.m. Saturday after a 24-year-old man jumped into the water with a friend.
He initially surfaced, showing immediate signs of distress and went under the water again and failed to resurface.
A search ensued, but officials couldn't find the man.
The Grotto has since reopened.