The US Sun AN Aussie maths boff has shown how he cracked the Zodiac Killer’s 1969 cipher, 50 years after the notorious killer slaughtered at least five people.
The infamous killer launched a reign of terror in northern California, USA, during 1968 and 1969 and despite his killing spree was never caught or identified.
The Zodiac Killer sent a series of letters and word puzzles to San Francisco newspapers up until 1974 to taunt the authorities.
Some messages were accompanied by fragments of clothing covered in blood as proof.
A total of four ciphers were sent but only one was solved, in 1969, with the killer saying he was carrying out the murders to collect slaves for the afterlife.
The remaining three coded messages have intrigued amateur detectives for more than 50 years who have hoped that solving them would lead to identifying the culprit.
Dr Samuel Blake, a mathematician from Melbourne, Australia, along with two other code breakers from the US and Belgium, have cracked the 340 cipher.
The coded message consists of 340 characters and was sent by the serial killer to the San Francisco Chronicle on November 8, 1969.
Blake said the fragment which led them to cracking the code were the words “GAS CHAMBER”.
Dr Blake, a visiting fellow at the University of Melbourne, initially got interested in the riddles after watching online videos by US cryptologist David Oranchak who had been working on cracking the code for 15 years.
Dr Blake told ABC News on Saturday: “It was sort of a way to get through the Melbourne Covid lockdown, was to play around with this in my spare time.”
He contacted Oranchak in March and then Dr Blake and his team started work on decoding the message, using the university’s supercomputer Spartan.
Dr Blake’s team tried 650,000 different ways to solve the riddle.
He said it was just by chance that they happened to stumble upon a fragment which indicated how the cipher could be solved.
In amongst the text were the words “GAS CHAMBER”.
Dr Blake said: “Using that fragment we were able to reverse engineer the entire solution, and got the entire message out from the Zodiac.”
The 340 Cipher message in full
“I HOPE YOU ARE HAVING LOTS OF FUN IN TRYING TO CATCH ME THAT WASNT ME ON THE TV SHOW WHICH BRINGS UP A POINT ABOUT ME I AM NOT AFRAID OF THE GAS CHAMBER BECAUSE IT WILL SEND ME TO PARADICE ALL THE SOONER BECAUSE I NOW HAVE ENOUGH SLAVES TO WORK FOR ME WHERE EVERYONE ELSE HAS NOTHING WHEN THEY REACH PARADICE SO THEY ARE AFRAID OF DEATH I AM NOT AFRAID BECAUSE I KNOW THAT MY NEW LIFE IS LIFE WILL BE AN EASY ONE IN PARADICE DEATH”
The message was written in capital letters, without any punctuation and included the misspelling of “paradise”.
The TV show the message refers to was The Jim Dunbar Show, a Bay Area television talk show at the time, CNN reported.
The Zodiac’s code was a homophonic substitution cipher, where large areas of text was replaced with symbols.
Dr Blake added that the Zodiac Killer made it even harder to solve by not writing the cipher in a left-to-right, top-to-bottom way as English is normally written.
Instead, the reading direction went down the diagonals of the page, from one row down and two columns across, to the next row down, two columns across.
He said: “Trying to stumble across that correct enumeration was one of the main difficulties.”
Dr Blake paid tribute to both Oranchak and Belgium-based software programmer Jarl van Eycke whose software program, azdecrypt helped crack the code.
While the message does not reveal the killer’s identity, it is hoped it may give clues to the authorities to help identify him.
Dr Blake and his team are now looking to see if their work on the 340 Cipher can be used to crack the remaining two messages.
One reads ‘My name is ____’ followed by 13-character cipher.
The other, called Z32, was a 32-character cryptogram also known as the “map code” as it was part of a letter warning of a buried bomb, accompanied by a map.
The Zodiac claimed he had killed as many as 37 people.
In an October 13, 1969 description, police said the killer was a five-foot-eight man aged 35 to 45, who had brown hair – with possibly a tint of red – and needed glasses.
After the latest cracked code came to light this week, the feds’ issued a statement acknowledging the achievement.
“The FBI is aware that a cipher attributed to the Zodiac killer was recently solder by private citizens,” it read.
“The Zodiac Killer remains an ongoing investigation for the FBI San Francisco Division and our local law enforcement partners.
“The Zodiac killer terrorized multiple communities across Northern California and even though decades have gone by, we continue to seek justice for the victims of these brutal crimes.
“Due to the ongoing nature of the investigation, and out of respect for the victims and their families, we will not be providing any further comment at this time.”
Another one of the cypher puzzles solved in 1969 by a California school teacher and his wife read: “I like killing because it is so much fun.”
