Chicago fire officials on Wednesday morning said a person was being evaluated after being pulled from Lake Michigan.
Crews were called to Diversey Harbor, on the 2600 block of Cannon Drive, at about 5 a.m.
A 66-year-old man was taken to Presence Saint Joseph Hospital, a fire department spokesman said. His condition was not known as of 5:45 a.m.
A police department spokesperson said officials believe the man was attempting to take his own life.