A team of volunteer codebreakers, including an Australian man, has cracked a mysterious cipher sent more than 50 years ago to a newspaper by the San Francisco serial killer who called himself Zodiac, the FBI says.
The Zodiac Killer—who was never caught—shot or stabbed seven people in the San Francisco Bay Area over the course of about year in 1968 and 1969, killing all but two of them.
During his murderous spree, he sent a series of terrifying letters to the San Francisco Chronicle newspaper.
Some of the notes were in code, including a particularly complex missive with 340 characters that became known as the 340 cipher.
“I hope you are having lots of fun trying to catch me,” said the cipher, cracked last week by codebreakers David Oranchak, Melbourne man Sam Blake, and Jarl Van Eycke, according to a video posted on YouTube by Oranchak.
“I am not afraid of the gas chamber because it will send me to paradice (sic) all the sooner because I now have enough slaves to work for me.”
Like the murders themselves, solving the Zodiac ciphers has become an international fixation for true-crime followers.
Oranchak, a 46-year-old web designer who lives in Virginia, said in the video he had hoped the cipher would yield information about the killer’s identity.
“The message doesn’t really say a whole lot,” he said. “It’s more of the same attention-seeking junk from Zodiac.”
ABC reported that Blake worked on decoding the message using a University of Melbourne supercomputer called Spartan.
“During the year we tested, by trial and error, around 650,000 different reading directions through the cipher. This search turned up — more or less — nothing,” Blake said. “However, one of these searches uncovered a surprising combination of words: GAS CHAMBER. That such a macabre phase should pop up in a sea of noise warranted further attention.
“From this fragment, David, Jarl van Eycke and I reworked the key and corrected an error Zodiac made in his diagonal enumeration of the second vertical segment of the cipher.
“Jarl’s fantastic program, azdecrypt, was essential in this process,” Black said.
The San Francisco office of the FBI on Friday confirmed the group had cracked the coded message, and said the investigation into the half-century-old case was ongoing.
“The FBI is aware that a cipher attributed to the Zodiac Killer was recently solved by private citizens,” the FBI said in a statement posted on Twitter. “The Zodiac Killer terrorised multiple communities across Northern California, and even though decades have gone by, we continue to seek justice for the victims of these brutal crimes.”
No one was ever charged in the Zodiac case, and theories abound as to the killer’s real identity.
The case has inspired numerous books and movies, including 1971’s Dirty Harry starring Clint Eastwood and 2007’s Zodiac with Robert Downey Jr.
Epoch Times reporter Caden Pearson contributed to this report.