A California woman stepped forward to say that her late father was the notorious Zodiac killer and she as a little girl wrote and stamped some of the letters he sent to taunt police.
Deborah Perez also said Wednesday that she embroidered the mask her father, Guy Ward Hendrickson, used during some of the murders, according to FOX affiliate KTVU in San Francisco.
Lawyer Kevin McLean told reporters that he has conducted a two-year investigation into Perez's claims that her dad — a carpenter and father of six children who was prone to violence — was the Zodiac killer, according to KTVU.
Hendrickson died in 1993 of cancer.
"He was a Jekyll and Hyde," McLean said. "He was nuts. He set out to kill people. Some of these killings were not random."
Perez came forward Wednesday because an investigator in Sacramento was about to put forth a different story about the murders and because she is currently working on a documentary about the spree, according to McLean.
San Francisco homicide detectives said they're investigating the information from Perez, of Southern California, about the infamous serial killer who terrorized the Bay area four decades ago.
Sgt. Lyn Tomioka said the investigation into the 1969 death of San Francisco taxi driver Paul Lee Stine related to the Zodiac killer remains ongoing.
"We get a significant number of calls a year. We will look into whatever evidence that is presented to us," Tomioka said about the case that also inspired a hit movie in 2007.
During a frenzied news conference outside the San Francisco Chronicle on Wednesday, Perez, of Corona, California, said she has given police what she believes are Stine's eyeglasses and letters she wrote — some to the newspaper — on her father's behalf about the crimes.
Perez claims she was a naive 7-year-old tagging along with her father during the killings.
"He told me he was sick, and all I wanted to do was help my dad," said Perez, who came to her conclusion about two years ago. "He kept telling me he was sick and he killed many, many people. I had no idea."
She said she could not keep her father's secrets any longer.
"There were strange events with my father," she said. "I would hear shots and my father would say it was firecrackers." She said he apologized on his death bed for doing "bad things," but didn't know then that he was referring to the Zodiac slayings.
Perez told reporters that she wove together the mask her dad wore during some of the vicious killings and saw a scrapbook when she was a little girl that seemed to indicate he had killed as many as 30 to 40 people, according to KTVU.
"Everyone is going to say she is crazy, but we had psychologists examine Ms. Perez," McLean said.
The self-described Zodiac killer — who gave himself that name in his letters to detectives — is blamed for at least five murders in 1968 and 1969.
He was never caught, though many believe he was Arthur Leigh Allen, a convicted child molester who died in 1992.
Click here for more on this story from KTVU.com.
The Associated Press contributed to this report.