A Chicago Fire Dept. dive team rescued two people from the North Branch of the Chicago River early Saturday in Ravenswood Manor.
Crews were called to a report of a person in the water about 11:15 p.m. near the 2800 block of West Leland, fire officials said.
Divers found the pair more than an hour later. One was taken in fair condition to Swedish Covenant Hospital, and the other was taken into police custody, officials said.
Chicago Police did not immediately have information on the rescue or arrest.