MARIETTA, Ga. (AP) — The more than 50-year mystery of who killed a young Georgia girl has been solved, authorities said.

Cobb County District Attorney Flynn D. Broady Jr., at a news conference Monday, confirmed the killer of 9-year-old Debbie Lynn Randall — whose body was found Jan. 29, 1972 — was William B. Rose, 24, of Mableton.

Detectives said the then-third grader was walking home Jan 13, 1972, from a laundromat, about a half-block away, when she was abducted, raped and strangled to death. A near-citywide search for Randall was initiated and included about 4,000 volunteers. A group of Southern Tech students found her remains 16 days later.

Marietta police followed up on hundreds of leads without success. In October 2001, detectives sent a hair removed from Randall’s body for DNA testing. The Cobb County Cold Case Unit received the case in 2015. In May of that year, a piece of clothing from Randall was sent for an updated test. Both pieces of evidence were then used to create a partial profile of a suspect. After many years, a familial DNA profile was found. Rose’s body was exhumed, and DNA tests confirmed he was responsible for Randall’s death.

Rose committed suicide in 1974, two years after Randall’s murder, authorities said.

At the news conference, Broady expressed sorrow for Randall’s parents who didn’t get the chance to know the case had been solved. Randall’s mother, Juanita, died of leukemia in 2018; her father, John, died in 2022.

“The loss of a loved one, especially one of such a tender age is difficult to comprehend. This family has waited for decades for an answer. This information will not replace the pain of losing Debbie Lynn,” Broady said.

Randall’s brother spoke briefly to reporters, WSB-TV reported.

“I wish my mother was here but I know she’s in heaven now and it’s finally over and we want to say we thank all of you for what you’ve done in making this day come to pass,” Marvin Randall said.