A North Carolina Teacher And Her Young Son Were Murdered In 1984. Now, Police Say They've Arrested A Suspect.

A young mother and her son were strangled to death in their North Carolina apartment nearly 40 years ago and police have announced new DNA testing has led to an arrest in the cold case.

In 1984, Sarah Mobley Hall, a 27-year-old special needs teacher, and her boy, Derrick Mobley, were found dead in their home in Hidden Valley, according to the Charlotte-Mecklenburg Police Department.

Capt. Joel McNelly, CMPD’s Violent Crimes Division commander, said during a recent press conference that James Thomas Pratt, 60, has been arrested in connection with the murders.

To identify Pratt as a suspect, CMPD’s Cold Case Unit said they used new familial DNA technology, which matches DNA collected at a crime scene to an entire genealogical family line and then, through investigative means, narrows down a pool of potential persons of interest whose biographies fit the facts in a case. McNelly said this was the first time this technology was used to solve a murder in North Carolina.

At the time of the murders, Pratt was nearly 22 years old and police did not consider him a suspect in the original investigation. However, he did live in the neighborhood and he was thought to have a “friendly relationship” with Hall, McNelly said.

Police did not comment on how they collected DNA from Pratt and they are still working to determine a possible motive in the case.

While Hall’s parents died before a suspect was arrested for the cold case murders, police notified the slain woman's surviving siblings of Pratt’s arrest.

“I carried a burden for years because I felt like I should have been with her. It would have never happened if I was with her,” Mary Dae said of her sister and nephew's killings, The Charlotte Observer reported.

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Police Chief Johnny Jennings, one of the original investigators on the case, said in a video statement that solving what happened to the mother and son "really tugged at me" during the many years he's worked on it.

"I should be retired somewhere getting a phone call that they solved this case," he said, "but I’m still working with CMPD, and we were able to bring closure to this case, and to be able to see that through as chief of police is just amazing."

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