.
"I just don't think there's any other way anybody would have figured it out."
The killer earned his nickname by signing his fourth letter to the press with "Zodiac" on August 7, 1969.
In it, he wrote: "Dear Editor This is the Zodiac speaking."
He also signed his letters with a circle and a cross over it, resembling a target or a coordinate symbol.
CASE SOLVED?
Authorities believe the Zodiac claimed his first two victims on December 20, 1968, when 17-year-old David Arthur Faraday and 16-year-old Betty Lou Jensen were shot and killed in Benicia.
The second two victims - Michael Renault Mageau, 19; and Darlene Elizabeth Ferrin, 22 - were found shot in a parking lot in Vallejo on July 4, 1969. Ferrin was killed and Mageau survived.
Nearly three months later, 20-year-old Bryan Calvin Hartnell and 22-year-old Cecelia Ann Shepard were found stabbed at Lake Berryessa in Napa County on September 27, 1969. Shepard was killed and Hartnell survived.
Taxi driver Paul Lee Stine, 29, was shot and killed in his car in San Francisco's Presidio Heights neighborhood on October 11, 1969.
The Case Breakers have asserted that the Zodiac is also responsible for a sixth killing in Riverside, California, on October 31, 1966.
Cheri Jo Bates was 18 years old when she was found dead in an alley on the Riverside City College campus.
In 1967, police received a handwritten letter which later led them to believe Bates' killing may have been committed by the Zodiac.
That theory was quashed in 2016 when investigators received an anonymous note from someone who claimed they'd written the earlier note as a "sick joke."
However, the Case Breakers have maintained that the Zodiac did kill Bates and claim investigators have blocked them from comparing her DNA to Poste's.
Maths boff reveals how he cracked Zodiac Killer's 1969 coded message 50 years after serial killer's deadly spreeWe pay for your stories!
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