From about 6:15 this morning, the Coast Guard was searching for two males in the water a mile south of Meigs Field, or around 31st Street. Later in the day, one was found dead, according to the Chicago Tribune. The search for the other man continued throughout the day. Two women had been recovered alive earlier.
According to the Tribune, the two men and two women went swimming around 2 a.m. when the sailboat they were on drifted away. The two women treaded water until daybreak when a sport fisherman picked them up.
The boat was found around the 63 Street water intake crib, and according to an Examiner.com source, was towed back to DuSable Harbor. The Tribune reported that the four people did not own the boat but had permission to use it.
For more information read the Chicago Tribune article.