A California man who took a polygraph test denying his involvement in a sadistic murder nearly 50 years ago has been identified as the suspected killer.

Esther Gonzalez, 17, was raped and bludgeoned to death while walking from her parents’ house in Beaumont to her sister’s house in Banning on February 9, 1979. The Riverside County District Attorney’s Office said.

Her body was found “dumped in a blanket of snow” along Highway 243 in Banning the next day, after an unidentified man called the sheriff’s department to report he had found a body.

Deputies said he was “argumentative” and declined to say whether the victim was a man or woman.

After five days of investigation, police identified the caller as Randolph “Randy” Williamson, whom they asked to submit to a polygraph test.

“He agreed and was successful, which, at the time, cleared him of any wrongdoing,” the district attorney’s office said.

Williamson, a veteran of the United States Marine Corps, then spent the next 35 years living a normal life, before moving to Florida, where he died in 2014.

But California detectives continued to work the unsolved case and determined earlier this year that “although Williamson was apparently exonerated by polygraph in 1979, he was never exonerated by DNA because the technology had not yet been developed.

Randolph “Randy” Williamson, who passed a polygraph test denying his involvement in the grisly 1979 murder of 17-year-old Esther Gonzalez, has now been identified as her probable killer.

Gonzalez was raped and bludgeoned to death while walking from her parents’ house in Beaumont to her sister’s house in Banning on February 9, 1979.

The break came last year when homicide detectives sent various pieces of evidence to Othram, Inc. in Texas to conduct a forensic genealogy, which they hoped could lead them to the killer.

Among the DNA samples sent to the lab was a blood sample taken during Williamson’s autopsy after his death in 2014.

It turned out to be a match to the semen sample taken from Gonzalez’s body, which had previously been uploaded to the Combined DNA Index System, which catalogs DNA samples.

It’s unclear whether Williamson knew Gonzalez or had a motive to kill her.

Police said they found old assault allegations against Williamson, but he had no convictions for violent crimes and his DNA never matched any of his rapes or murders. reports the Los Angeles Times.

Officials with the District Attorney’s Office are now seeking information on Williamson, Gonzalez and “other potential victims.”

But they say they’re happy to have found an answer for Gonzalez’s family after all these years.

“This murder still haunts them,” Jason Corey, an investigator with the district attorney’s office, told the LA Times. “But Esther was never forgotten by us all these years.”