A 26-year-old Detroit man is dead after drowning at Cass Lake in Keego Harbor, Michigan, on Sunday, according to the Oakland County Sheriff's Office.

The county's search and rescue team responded to the lake around 4:15 p.m. after a 911 call. 

The man was on a boat with four other people, the sheriff's office said in a written release. The boat had been trolling over a sandbar, but it later moved to deeper water.

"The man was apparently unaware the boat had moved and entered the lake, where it was 55 feet deep, and he lost contact with the boat," the sheriff's office said.

Officials say the man didn't know how to swim. 

One of the man's friends on the boat jumped in to help him, according to the sheriff's office. The man was allegedly panicking, and his friend couldn't keep him above the surface.

The sheriff's office says "conflicting information" about where the man went into the water "hampered" the rescue attempt. 

Rescue personnel eventually found the man and began CPR on him once he was taken out of the water. 

The man was taken to the hospital where he later died.