The 89-year-old man was found floating by a secluded dock near Diamondhead and is believed to have been in the water for several days.
Deputies believe he was working on the dock when he fell into the water; tools and fresh boards were found nearby.
"When we arrived on scene we found the male floating still behind his residence, by his dock," said Lt. Tim Cade with Montgomery County Precinct 1. "Any time you have an incident like this, a death, it's just a tragic situation."
Authorities do not suspect foul play in the man's death. An autopsy will be conducted.
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