GRAND BEND, Ont. -- A search is resuming for a missing swimmer on Lake Huron, just north of Grand Bend.

Lambton OPP say two men, who were not wearing life jackets, got into trouble in waves and wind when they went swimming off a pleasure boat Sunday afternoon.

One man was rescued by passengers on the boat, but the second slipped under water.

Emergency personnel responded after witnesses on shore saw flares shot from the vessel.

The search that included helicopters Sunday evening failed to find the man.