A California serial murderer known as the “Alphabet Killer”, convicted of slaying four women in 2013, may have actually killed 26 women, according to shocking new revelations from a fellow death row inmate.

Joseph Naso, a former photographer, was convicted and sentenced to death for the murders of Roxene Roggasch, Carmen Colon, Pamela Parsons, and Tracy Tafoya. The crimes, committed in the 1970s and 1990s, earned him his chilling nickname because each victim’s first and last names began with the same letter.

During his trial, prosecutors presented disturbing evidence discovered at Naso’s California home in 2009, including photographs of lifeless bodies, journals describing rape and torture, and a handwritten list referencing 10 women.

Despite the damning evidence, Naso—who represented himself—insisted, “I am not the monster that killed these women.” He was sentenced to death in 2013. Read more from The Independent.

Alphabet Killer Confesses from Death Row

According to Oxygen’s new documentary, Death Row Confidential: Secrets of a Serial Killer, fellow death row inmate William Noguera claims Naso confessed to killing far more women than previously believed.

"He’s guilty of more murders than anyone knows. He told me everything, and I wrote all of it down," Noguera says in a preview clip. Noguera befriended Naso while participating in a program assisting elderly prisoners. Over a decade, Naso allegedly revealed that his true victim count was 26, not just the four confirmed cases.

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

Investigators later discovered a coin collection with 26 gold heads at Naso’s home, which Noguera claims represented his “trophies” for each of his victims.

Renewed Investigation into Forgotten Victims

After gathering Naso’s alleged confessions into a 300-page document, Noguera passed the material to retired FBI task force investigator Ken Mains, who now appears in the Oxygen series. Authorities are examining whether the new details could connect Naso to more unsolved cases of murdered women in California.

Despite the mounting evidence, Naso—now in his late 80s—remains on death row at San Quentin and has not commented on the allegations of additional killings.

A Legacy of Fear

The victims officially tied to Naso—Roggasch, Colon, Parsons, and Tafoya—were all sex workers, adding another layer of vulnerability to their tragic fates. Their stories, along with the possibility of dozens more, highlight the brutal scope of Naso’s crimes.

"These women deserve justice, whether it’s four or 26," investigator Ken Mains said. "We cannot forget them."

For more background on Naso’s crimes.

The Murder List (IMDb) 

‘Alphabet killer’ Joseph Naso sentenced to death for decades-old murders of four women | The Independent | The Independent

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