A team of cryptography enthusiasts announced on Friday they had successfully cracked one of the coded messages sent over 50 years ago by the "Zodiac Killer," who terrorized northern California in the late 1960s and remains unidentified.
The message was sent in November 1969 to the San Francisco Chronicle newspaper by the alleged serial killer, its code consisting of a series of cryptic letters and symbols.
Sleuths hoped the coded message contained the identity of the killer, who committed at least five murders in 1968 and 1969 but claimed 37 in total and inspired other serial killers.
According to the trio said to have broken the code, the message includes boasts and defiance of authorities without any real clues on motive or identity.
It includes to message: "I hope you are having lots of fun in trying to catch me... 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."
It took several computer programs and years of work for David Oranchak, a 46-year-old American web designer, to decipher the complex code he started working on in 2006.
He was helped by Sam Blake, an Australian mathematician, and Jarl Van Eykcke, a Belgian logistician, he told the San Francisco Chronicle, which confirmed the discovery with the FBI, the federal agency in charge of the investigation.
A first message sent to Californian newspapers was decoded by a schoolteacher and his wife in 1969.
"I like killing because it is so much fun," it said, again referring to "slaves" that he claimed to collect to serve him in the afterlife.
But the code used in the first message was much simpler than the one for "340 cipher," so called because it contains 340 characters spread throughout 17 columns.
"All of us in the crypto community on the Zodiac figured the cipher had another step beyond just figuring out what letters belonged to the symbols, and that's just what we found here," said Oranchak.
The 340 cipher is read diagonally, starting from the upper-left corner and shifting one box down and two boxes to the right.
When the bottom is reached, the reader must go back to the opposite corner, said the expert in a video posted on his YouTube channel.
According to him, the coding system appears in particular in a cryptography manual for the US army dating from the 1950s.
Zodiac Ciphers: Messages from a murderer
The 1960s of the Bay Area of California are often remembered as a time of love and social expansion, but there remains a terrible and unexplained stain on the otherwise illustrious history. A lone and extremely elusive killer wandered the Bay Area streets at night. Known as the Zodiac killer, because of his messages signed with a zodiac symbol, he became one of the most infamous and terrifying killers in history. While he claimed to be responsible for the killings of 37 people, investigators were only able to confirm only seven victims (five were murdered, two survived). Throughout his serial killings, the Zodiac killer would write letters to the Bay Area press in an attempt to brag and taunt his pursuing officers. But these weren’t any ordinary letters. They were ciphers. From the late 1960s to the early 1970s the Zodiac killer sent four coded letters. Of the four ciphers, only one has actually been solved.
His letters were written in two parts. The first part was usually written in plain text, while the other was in cipher text, in which he claimed contained his identity. In the plain text part, he threatened newspapers to publish his letters or else he would kill more innocent people. In other segments of his letters, he listed the names of his next victims, creating havoc amongst the Bay area. His goal was to use the media to instill fear in Bay area citizens, and it worked. As cryptographers dug deeper into his letters, they were able to find out what drove the Zodiac killer to keep killing.
Of the four ciphers letters he sent, one was a three-part coded message, sent to three different press companies, making a 408-symbol cipher. His other famous cipher letter contains a 340-character cipher, which still doesn’t have a definitive solution. After the Zodiac killer sent his 408-symbol cipher (Z408), he sent another message to the police stating that if they could solve that cipher “they will have me.” To understand what the Zodiac killer meant by this, we will have to first see how the message was deciphered.
In 1969, two schoolteachers Donald and Bettye Harden managed to crack the Z408 cipher which consisted of random symbols corresponding to a plain text message. The cracked code offered frightening insight into the Zodiac killer’s mind. According to the plain text message, he was attempting to collect slaves for the afterlife.
