Zodiac Killer message known as '340 Cipher' solved after 51 years

A three-person team appears to have unraveled a previously unsolved cryptogram from the Zodiac Killer, who killed at least five people in Northern California in 1968 and 1969. The coded message, known as the "340 Cipher" because it contains 340 characters, was sent in a letter to the San Francisco Chronicle in 1969. 

"I hope you are having lots of fun in trying to catch me," reads part of the message, according to David Oranchak, a member of the team that cracked the cipher. The message also references not being afraid of death, but doesn't offer up a name or obvious clue as to the identify of the Zodiac Killer. 

Oranchak on Friday posted a video on YouTube explaining in detail how he and other other members of his team, Sam Blake and Jarl Van Eycke, solved the cipher. Their discovery, which was reported earlier by the Chronicle, was sent to the FBI earlier this month.

 The FBI on Friday confirmed that the cipher was solved by three private citizens. 

"On December 5, 2020, the FBI received the solution to a cipher popularly known as Z340 from a cryptologic researcher and independently verified the decryption," said the FBI in an emailed statement. "This cipher was first submitted to the FBI Laboratory on November 13, 1969, but not successfully decrypted. Over the past 51 years CRRU has reviewed numerous proposed solutions from the public -- none of which had merit."

CRRU is the FBI's Cryptographic and Racketeering Records Unit.

In a tweet Friday, the San Francisco office of the FBI said the Zodiac Killer case remains an ongoing investigation.