Serial killer John Wayne Gacy was convicted of murdering 33 young men and was executed in 1994. (WJBC file photo)

By The Associated Press

CHICAGO - A Cook County Sheriff's spokesman says investigators are a step closer to carrying out a search of the apartment complex where serial killer John Wayne Gacy's late mother once lived to determine if he buried any bodies there.

Cook County State's Attorney Anita Alvarez's office agreed late Friday to submit a request for a search warrant to a judge.

The office says investigators will use special equipment to search for indentations in the ground that might indicate something has been buried at the apartment complex on Chicago's Northwest Side. Highly trained dogs will then be brought in to sniff for human remains.

Gacy was convicted of murdering 33 young men who died in the 1970s. He was executed in 1994.