By Velena Jones

GROVELAND (CBS13) — In the quiet, tightly knit Tuolumne County town of Groveland, the rumors have circulated for years that the Zodiac Killer was a neighbor living nearby.

“This has been a 10-year-old rumor,” said Groveland resident Brian Pledsen.

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For Pledsen, Gary Poste was just the quiet neighbor who lived next door.

“Very introverted. It took a while for us to talk, but he and I talked quite a bit,” he said.

In the years Pledsen lived next to Poste, he never suspected Poste could be a killer.

“Too nice of a guy, too mellow, too nice, he hid it very well,” said Pledsen.

Gwen—a Groveland resident who did not want to disclose her last name—grew up with Poste and his wife Mary babysitting her. She lived next to the couple for years.

“I looked up to Gary Frances Poste as an uncle. I use to cut his hair. I spent nights at his house. I went hiking with him. He taught me how to drive,” Gwen said.

After a revelation from a 2018 conversation from Poste’s wife, who is now in a nursing facility, Gwen explained there is no question in her mind Gary Poste is the man some suspect him to be.

“One thousand percent, I do believe I grew up next to the Zodiac,” she said. “The first words out of her [Mary’s] mouth were ‘Gary is a very bad man and I’m sorry I didn’t tell the cops about what he has done.’ To me, that is an admission she knew.”

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While Gary Poste was never aggressive towards Gwen, she claims he took his anger out on his wife.

“He was aggressive with Mary and hit her sometimes when she made dinner the wrong way,” she explained.

Gwen, while confident Gary Poste lived a double life, was still heartbroken the man she considered family could be tied to the notorious serial killer.

“He had this way of caring for people, even though his other side, his other life, he was a monster,” she said.

A woman named Michelle who described herself as Poste’s daughter-in-law through marriage, also believes he is the Zodiac Killer. Michelle first learned about the suspicions around 7 years ago.

“I always knew he was twisted,” she said. “I just obviously didn’t think to this level. Who would?”

Michelle’s 10-year relationship with Poste’s son resulted in having a child. She claims during that relationship, Poste sent people to harass her and vandalize her property.

“He had windshields broken in my car, home window, my tires slashed, sugar in my gas tank. This kind of delinquent stuff because apparently he didn’t want me with his son,” she explained.

Michelle said she eventually moved out of California after repeated harassment.

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Poste has not officially been named as a suspect by any law enforcement agency.

Velena Jones