Two murder cases separated by 100 miles and unsolved for more than 40 years are now thought to be related, as investigators identified the remains of a woman found dead in Alabama and the circumstances of her murder.

Hunters in a wooded area off Old Pascagoula Road in Grand Bay, Ala., came across skeletal remains on Nov. 28, 1976. Though the woman’s identity was a mystery, investigators had several clues to work with.

"The skeleton still had the clothing and it was mostly intact and there was also a partial dental plate the skull of the female indicated pre-existing injuries from traffic collisions," Det. J.T. Thornton with the Mobile County Sheriff’s Office told WKRG-TV.

Eight months earlier and about 120 miles west, authorities began investigating the disappearance of 33-year-old Mary Ann Perez, who vanished after going out with friends to a local bar in Chalmette, located outside New Orleans, on March 26, 1976.

The wife and mother of three left her teenage daughter Donna to watch her younger children, saying she would call to check in later.

"Donna said she got a phone call from mama first, stating that she was okay and that she would be home shortly," Shannon Miller, Perez’s youngest child, said in an episode of "Unsolved Mysteries." "And then Donna said she got a phone call from a woman by the name of Dorothy."

"Dorothy" told Perez’s daughter her mother was having car trouble, but the family said the vehicle was new. The next morning, Perez’s car was found in the bar’s parking lot, and appeared to be running with no issues.

Perez’s purse was found three days later, weighted down by a brick in Lake Pontchartrain, about 10 miles away. Perez was nowhere to be found.

In 1980, a drifter named David Courtney admitted that he and his wife Donna killed five women in several states, and one of the murders appeared to echo the details surrounding Perez’s disappearance.

“When I went up to Kansas to interview David Courtney, he told me about the female he abducted in New Orleans,” New Orleans Police Det. Bob Lambert told “Unsolved Mysteries." "He stated that he was driving down the highway and pulled in the parking lot of a country-western bar."

Courtney claimed the woman was too drunk drive home and he convinced her to go with him. Courtney then picked up his wife and the three of them went back to the couple’s trailer.

"He stated that this female fell asleep on a chair in the trailer and there was some sexual advancements by his wife, which woke this female up and she became disturbed and irate and upset about what was going on and then they agreed to give her a ride home at that time," Lambert said.

As Donna Courtney drove, David Courtney said he strangled the woman in the back seat of their car and threw her purse over the side of the bridge they were crossing at the time. Courtney picked Perez’s picture out of a line up to verify she was the woman he killed, but Courtney said he couldn’t remember where they left her body.

“All the bodies he had presented in different locations, had been located,” Thornton told WKRG-TV. “The last one he presented (Perez), they hadn’t found her. So that was questionable at that time.”

The Courtneys said they believed they dumped the body either at the Louisiana-Mississippi border or the Mississippi-Alabama border, but without a body, Perez’s family held out hope that she was still alive.

“Maybe he might have strangled her unconscious, thinking that she was dead and threw her out. Maybe she got up several hours later. Maybe there’s a possibility that she is somewhere out there,” Miller told "Unsolved Mysteries."

It appeared the answer was in Mobile County, but prior to the computer age, lackluster communication between law enforcement agencies made it difficult to connect the “Jane Doe” found in the woods to Perez’s disappearance.

In 1977, investigators shipped the skeletal remains to a lab in Oklahoma to construct images of what the woman may have looked like. But the images produced no leads.

Though the case had long been cold, Det. Thornton found himself investigating the 1976 case this year.

“I actually went to investigate another Jane Doe that was found in ‘76,” Thornton told WKRG-TV. “And behind her, I found Jane Doe X2. So I thought there might be some correlation so I started investigating and found there was no correlation.”

But in his work, Thornton met a detective in Harrison County, Miss. who remembered the Perez case. Thornton went to New Orleans to speak with Perez’s family.

“They advised me that she had been in a traffic accident, Mary Ann Perez had, that she had a partial dental plate, and they presented me with the demographics of her and I thought that’s almost a perfect match," Thornton said.

The remains, at first thought to be lost, were found warehoused in Oklahoma and have been sent to a lab in Texas for DNA testing. Investigators are confident that the final results will come back in a few weeks with a match to Perez.

“It was actually a miracle,” Thornton said. “The state attorney general’s office sent an investigator down here, who also works cold cases. So when he comes in he’s like, 'Do you know anything about this case?’ And I said I do and I’ve been hunting for the remains. And he’s like, 'We’ve been looking for the case that goes with the remains.'

"That goes to show that no matter the time length, these cases can be solved," Thornton said.

The Courtneys were never charged with Perez’s death. They both pleaded guilty to murder in Wichita, Kan., in 1980. David Courtney is serving a life sentence in Kansas. Donna Courtney served 10 years for her part in the killings and died two decades ago.

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