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A Facebook page started by a California woman to solve the 42-year-old murder of her mother has rekindled interest in the case and generated information police say "needs to be investigated."

Melissa Carson was 8 years old when her mother was murdered in 1970, a case that was never solved. The crime has haunted Carson her entire adult life, plaguing her with two questions: Who did it, and why?

The now 51-year-old woman recently turned to social media to help crack the decades-old mystery -- and her efforts appear to have residents of the tiny California town of French Camp talking, investigators said.

"Somebody out there still knows something," Carson told FoxNews.com.

Her mother, Phyllis O'Brien Carson, was 32 with four children when she disappeared on Oct. 27, 1970, after visiting a popular bar called Francis Truck Stop in the small, close-knit community 77 miles east of San Francisco.

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Carson, who was out with her brother and sister, called home to check on her children and told relatives she was getting a ride home from a friend, whom she did not name. That was the last time she was heard from.

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Carson's body was found by pheasant hunters three weeks later. No suspect or motive were ever identified, Detective Chandra Bassett with the San Joaquin County Sheriff’s Office told FoxNews.com. Carson's remains were so badly decomposed that a cause of death could not be determined, she said.

"She was exposed to the elements for a length of time. There's a lot that we couldn't tell," said Bassett, adding that there is no forensic evidence left to be investigated.

"We've exhausted all of those possibilities," she said. "There's nothing forensically left to be done."

Carson, who learned of the gruesome details from investigators when she turned 18, said it is believed her mother was raped and then killed. Her capri pants were found inside out and appeared to be tossed from the side of Yettner Road. Her body was discovered partially clothed and in a position that suggests she was thrown from a vehicle, Carson said. Her personal belongings, including her wallet and jewelry, were also found, ruling out robbery as a motive.

Bassett said Carson's remains were found lying down an embankment off the road about five miles from her family's home. At the time of the murder, the area was rural, with heavy brush and only one house near the crime scene, she said.

Carson's father, who died in 1992, was long ruled out as a suspect. Over the years, Carson said she and her brother came up with theories and identified a few persons of interest -- none of whom ever came forward to take polygraph tests.

"I don’t think she would have left the bar with somebody she didn’t know," Carson said, noting that the killer "knew the area well."

After a local news outlet ran Carson's story last month, community members in the small town have been abuzz over the case. Investigators said an anonymous person has since come forward with information that police are probing.

"It's information that needs to be investigated, that's for sure," said Bassett, who declined to provide details.

"The local reports have brought it back up the surface in the community," she said of the case. "That gives me hope that somebody out there knows something."

Click here to visit the Phyllis O'Brien Carson Facebook page

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