OPP divers and marine units continued their recovery efforts Friday after a teenager went missing in the water off Port Stanley.

An 18-year-old London male, William Johnston, was swimming in Lake Erie with a 19-year-old female late Thursday afternoon at the main beach.

The woman made it to shore safely with help from lifeguards, but Johnston failed to make it to the beach.

Members of the Joint Rescue Coordination Centre (JRCC) Trenton, the Elgin County and Chatham Kent OPP Marine Units, the United States Coast Guard, and Ornge, have all helped in the search.

OPP Sgt. Dave Rektor says there is help in the air and under the water to try to find the teen.

“it’s a very difficult search, especially when the water is murky as it is. It’s extremely difficult if not impossible to see anything, so they are relying on feel. And they have been in there an awful long time, yesterday and now today as well.

"It’s our hope to reunite this swimmer with his loved ones."

As Johnston's family gathered on the beach Friday,  praying for his return, the red warning flags remained in place and people were still going in the water.

Rektor stressed that swimmers must pay attention to the red warning flags posted when it is dangerous to swim.

"Folks, the bottom line is…these waters can become very rough. The Great Lakes are notorious for becoming rough. There are undertows. Yesterday the flags were flying… warning people to stay out of the water. Those warnings need to be taken seriously. We can’t physically force people to stay out of the water."