PENTWATER -- Pentwater police are asking for your help Saturday, as they investigate reports of a missing swimmer.

At around 9:30am Sunday morning, witnesses tell authorities say saw a white man, with dark hair, and a sturdy build swimming in the waters at Charles Mears State Park Beach. A few minutes later, they say he was no longer visible.

Police conducted a search of the beach and surrounding area but did not find the man. If you have any information on this investigation, like the identity of the swimmer, you're asked to contact the Pentwater Police Department at (231) 869-4630.