Minneapolis Police Lt. Rick Zimmerman told KSTP-TV that the man appeared to be in his 20s, and that there was no sign of trauma. Boaters near Boom Island apparently spotted the man's body at around 1 p.m.
Several young men have lost their lives in the Mississippi's Twin Cities shores. Some of the deaths have been accidental, while others are believed to be homicides.
One such case was the 2002 murder of Chris Jenkins, whose body turned up in the Mississippi. Police concluded that he had been abducted and tortured before being dumped into the river.
The Jenkins case is one of several that have fueled the Smiley Face Killer theory -- the idea that a group of killers was targeting college-aged men and making their deaths look like accidents.