Marquis Johnson, 26, was taken into custody at approximately 3:10 p.m. for an outstanding warrant in Chicago.
He confessed to shooting his boyfriend and burying him in the yard of an abandon residence at 15817 Myrtle Avenue in Harvey.
Law enforcement officials found the body of an unidentified man at the address provided by the suspect.
Police say this was an isolated incident and there is no threat to public safety.
The identity of the victim has not yet been determined. Further information will be released as it becomes available.