Updated

After years of investigation, authorities are indicting a man in the 1975 slaying of a 9-year-old Girl Scout who disappeared while delivering cookies.

District Attorney Torry Johnson announced the indictment against Jerome Sidney Barrett on Friday. Barrett is already in jail after being charged in another 1975 slaying.

Marcia Trimble disappeared from her upscale neighborhood Feb. 25 of that year. She was found strangled 33 days later. Her body was sticking out from a plastic wading pool in a neighbor's garage.

The case has been Nashville's most notorious unsolved murder for 33 years.

Barrett is awaiting trial in the killing of Vanderbilt University student Sarah Des Prez.

Click here to read more from FOX affiliate WZTV-TV.