Serial killer claims he murdered 26 women as new documentary reveals dark secrets

One of California's most notorious killers is back in the spotlight as a new documentary revisits his crimes and uncovers even darker secrets.

Joseph Naso, the former photographer convicted in 2013 of killing four women, is now claiming he actually killed 26 women. The bombshell confession comes from a fellow death row inmate, William Noguera, who spent more than a decade building trust with Naso inside California's infamous San Quentin State Prison.

The chilling revelations are featured in a new Oxygen documentary, "Death Row Confidential: Secrets of a Serial Killer," premiering Sept. 13.

"He's guilty of more than anyone knows," Noguera says during a preview of the new series. "He told me everything, and I wrote all of it down." 

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Naso's double life stunned the country. He was a father of two, Little League coach, and school photographer by day - and a sadistic killer by night. Investigators found photographs of what appeared to be dead women among his belongings, along with what investigators dubbed a "hit list," containing ten cryptic descriptions of female victims.

Even after a jury handed down a death sentence, Naso continued to maintain his innocence in interviews, including an exclusive interview with KGO.

Noguera, who is also on death row for a 1983 murder, was assigned to assist elderly prisoners as part of a prison disability program, which is where he connected with Naso. Over 10 years, the two developed what was described by several media outlets as an "unusual" relationship. 

Noguera told the outlet that Naso eventually opened up, and offered the stunning admission.

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"When I told him, 'Well, look, they got you because a list of 10,' he started laughing," Noguera recalled. "He said, 'They got it all wrong. Yeah, I killed them women, yes. But those aren't my top - those aren't my list of 10. Those are my top 10." 

Noguera disclosed even more disturbing details, noting that Naso's claims of killing 26 women may be supported by something reportedly found in the search of Naso's home. Noguera told the outlet, "They found a coin collection with 26 gold heads. Those represent his trophies, they represent the 26 women that he murdered."

Determined to document everything, Noguera compiled a 300-page dossier filled with cryptic clues, locations and partial confessions. He passed the files to retired FBI task force investigator Ken Mains, who took on the case pro bono.

While Naso never named his victims, his rambling stories hinted at forgotten crimes. In one ploy, Noguera convinced him to put a confession in writing, dangling the possibility of a prison transfer to get closer to his sons.

In his own words, Naso reportedly described luring a woman through a modeling ad, driving her home, killing her and dumping her body under the Richmond-San Rafael Bridge.

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The description matched the disappearance of Berkeley woman Lynn Ruth Connes in the 1970s, KGO noted. She had answered a modeling ad, and her bike was later found chained near the exact spot Naso described.

Working together, Detective Mains and Noguera linked Naso to several cold cases, including Connes'. Piece by piece, they are putting names to the women Naso once reduced to cryptic notes - and delivering long-awaited answers to grieving families.

"But now they know what really happened to her," Noguera said. "And that has been my goal the whole time, is to give the victim's family just that closure, that finalization, that's the whole motivating factor behind all of this."

Naso, who was dubbed the "Alphabet Killer," gained his grim nickname after being found guilty in 2013 of murdering four women whose first and last names began with the same letter. The victims included Roxene Roggasch, 18, Carmen Colon, 22, Pamela Parsons, 38, and Tracy Tafoya, 31, with their deaths occurring between 1977 and 1994.

Authorities had previously investigated Naso in connection to the unsolved "Alphabet Murders" of three young girls in his hometown, Rochester, New York, in the 1970s. However, DNA evidence ruled him out as a suspect in those cases.

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Investigators also uncovered a diary detailing more than 100 sexual assaults dating back to the 1950s, many involving underage girls. With the new claims emerging, law enforcement agencies across California and the FBI are now re-examining unsolved cases.

"Our two minds, cop and convict, working together. I know that I can solve unsolved murders. Let's get them," Mains said. 

As the documentary reveals, Naso's crimes may stretch further than anyone ever imagined - and his disturbing legacy continues to haunt both investigators and families seeking closure.