Dec 14, 2020 I Paul Seaburn

The Zodiac Killer’s Secret Code Has Finally Been Cracked

It’s been over 50 years since the first death attributed to the serial murderer who became known as the Zodiac Killer, and over 40 since his last murder in the San Francisco Bay area – leaving his total at five confirmed dead, two injured and as many as 37 possibly attributed to him. Yet the pseudonym he chose for himself, “Zodiac,” still strikes terror in northern California and around the U.S. as his story was one of the first to be widely spread by the national media and because of his threatening, frightening and partially cryptic letters to San Francisco newspapers. Adding to his mystique, those coded messages have resisted being cracked by the best cryptographers … until now.

“Last weekend, we solved the 340 and submitted it to the FBI. They have confirmed the solution. Authorities have spent the time since then making the appropriate notifications to the victims’ families.”

On November 8, 1969, the Zodiac Killer mailed a card to The San Francisco Chronicle with a cryptogram consisting of 340 characters, which soon became known as "Z-340," “the 340 Cipher” or just “the 340.” A previous 408 character cryptogram, sent in thirds in three letters, had been broken quickly. The 340 resisted deciphering by professionals until recently when amateurs David Oranchak, a Virginia software developer and operator of a website dedicated to the code, Sam Blake, an applied mathematician in Melbourne, and Jarl Van Eycke, a warehouse operator and computer programmer in Belgium announced they had solved it – a fact confirmed by the FBI.

4abc   San Francisco Chronicle Dripping Pen Card November 8 1969 340 Cipher COLOR
The 340 Cipher

Van Eycke wrote the code-breaking software, while Blake and Oranchak ran an estimated 650,000 possible solutions through it without success until December 3rd, when the program finally began spitting out recognizable words and phrases, such as “gas chamber” and “trying to catch me.”

Before we reveal the decoded message, let’s do a quick summary of the Zodiac Killer’s history. The first murders attributed to the Zodiac Killer were the shootings of high school students Betty Lou Jensen and David Faraday on December 20, 1968. After another murder and attempted murder six months later, someone claiming to be the killer called the local police, beginning the infamous cat-and-mouse game between Zodiac and the authorities. The first three letters were received by the media on August 1, 1969, and published. On August 8, Donald and Bettye Harden of Salinas, California, cracked their 408-symbol cryptogram. After more murders, the card containing the 340 was received. The letters continued until 1974 as more killings were linked to the Zodiac Killer but not confirmed. In April 2004, the San Francisco Police Department marked the case "inactive." In 2018, the Vallejo Police Department announced plans to collect the Zodiac Killer's DNA from the back of stamps he used but no results have ever been reported. While many people were investigated and many suspects were named, none have ever been proven to be Zodiac.

“I hope you are having lots of fun in trying to catch me that wasn’t 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.”

That’s the message (with the misspellings) decoded by Van Eycke’s program and confirmed as authentic by the FBI. The TV show the message refers to is "The Jim Dunbar Show," a Bay Area television talk show that a person claiming to be the Zodiac Killer had called into two weeks before the card and the code were sent. Oranchak told The New York Times he was not optimistic about decoding two more very short ciphers attributed to the Zodiac Killer, but solving 340 might help. Will it help to finally find the killer?

"Due to the ongoing nature of the investigation, and out of respect for the victims and their families, we will not be providing further comment at this time."

As per its tweet, the FBI San Francisco Division is still on the case.

Could this prompt the Zodiac Killer, if he’s still alive, to come out of retirement and strike again? In 2020, anything can happen.

Paul Seaburn

Paul Seaburn is the editor at Mysterious Universe and its most prolific writer. He’s written for TV shows such as "The Tonight Show", "Politically Incorrect" and an award-winning children’s program. He's been published in “The New York Times" and "Huffington Post” and has co-authored numerous collections of trivia, puzzles and humor. His “What in the World!” podcast is a fun look at the latest weird and paranormal news, strange sports stories and odd trivia. Paul likes to add a bit of humor to each MU post he crafts. After all, the mysterious doesn't always have to be serious.

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