An off-duty Michigan Department of Natural Resources conservation officer risked his life to save a swimmer from strong Lake Superior currents last weekend, officials said Thursday.

Mark Zitnik and his family were boating on Munising Bay in Alger County on Saturday when he heard someone yell for help as their boat navigated around a sandbar off Sand Point Beach, the department said in a statement.

Zitnik, who patrols Alger County and has been with the DNR Law Enforcement Division since January 2015, jumped into “search and rescue” mode and saw people onshore pointing toward two swimmers struggling in the water about 200 yards away, according to the release.

"The swimmers had been wading in shallow water covering a sandbar, but they ended up in deep water with a strong current," the DNR said. "Accelerating the boat to reach the swimmers, Zitnik dove from the moving vessel once he was 10-15 yards from the swimmer who appeared be having the most trouble."

Using a water hold technique he learned at the conservation officer academy, Zitnik wrapped his arm around the man’s chest, which "caused the swimmer to begin to panic even more, resisting the rescue attempt," department officials said. "Zitnik identified himself as a conservation officer and rescue swimmer in an attempt to calm the man. After a brief struggle, Zitnik swam the man back to the boat."

Passing boaters helped the second swimmer. Both swimmers were transported back to shore.

“A conservation officer is never truly off-duty,” said DNR Law Enforcement Division Chief Gary Hagler. “Officer Mark Zitnik is a prime example of the training and dedication that all conservation officers commit to. Without hesitating, he risked his life while with his own family to save these two men.”

The rescue came as DNR officials are warning people to stay safe on state waterways, citing several drownings and near-drownings in Michigan this summer.