The cases involve the killings of Marebeth Welsh in 1993 and Jennifer Persia in 1994. Authorities said advances in investigative genetic genealogy connected the crimes and pointed to the same individual as the suspect.
"It was very unexpected," said Melody Beth Welsh, Marebeth's daughter. "But grateful for all their hard work."
Family members had long feared they might never learn who was responsible for the deaths. On Thursday, Camden County prosecutors said renewed DNA testing provided a breakthrough.
"As a result of investigative genetic genealogy testing and additional interviews, a suspect was developed and tentatively identified as Francis T. Schooley," said Det. Daniel Crawford of the Camden County Prosecutor's Office.
Welsh, 24, of Woodlynne, was found strangled and sexually assaulted in Camden in 1993. DNA was collected from her body at the time, but no matches were found. The following year, 16-year-old Jennifer Persia was found stabbed and strangled in her Magnolia home, a crime that deeply affected the small community.
In a 1995 Action News report, Persia's mother spoke about the loss.
"I can't imagine what kind of animal did this to my daughter," said Georgia MacNeir.
DNA evidence was also collected in Persia's case and later entered into the FBI's CODIS system, but it did not produce any matches. Investigators said that changed last year, when clothing from Welsh's case was retested. The resulting DNA profile was entered into the FBI system and matched an unknown male profile from Persia's case.
Further investigation, including interviews and DNA swabs from family members of the suspect, led detectives to conclude that Francis Schooley of Mantua was the source of the DNA in both cases. Authorities said Schooley would have been charged if he were alive. He died by suicide in 2000 at the age of 39.
For investigators and families, the development was emotional.
"Comforting to be able to go to Mark (Persia's father) with some good news and go to the Welsh family as well," said Sgt. Dennis Convery of the Camden County Prosecutor's Office. "It touches me."
Detectives said Schooley had ties to Jennifer Persia's stepfather and had also been seen with Marebeth Welsh before her death. While the suspect cannot face charges, authorities said the identification provides resolution to two cases that haunted South Jersey families for decades.