Washington, Dec 12 (IANS): The Federal Bureau of Investigation (FBI) has announced that 51 years after the self-proclaimed 'Zodiac Killer' randomly killed five people in Northern California's Bay Area, a team of amateur codebreakers have solved a cryptic cipher sent to the San Francisco Chronicle newspaper in 1969, according to media reports.

According to an archived FBI statement, the 'Zodiac Killer' sent local newspapers a three-part coded message explaining his motive for the killings in 1969 and in a separate letter to the editor suggested his identity was buried within an elaborate cipher message.

The decoded message revealed the killer's twisted motive, but his identity remains a mystery.

In its announcement on Friday, the FBI said that the "340 cipher" was solved by three codebreakers -- David Oranchak, a software developer in Virginia; Jarl Van Eycke, a Belgian computer programmer; and Sam Blake, an Australian mathematician, CNN reported.

After the decoding, it was revealed that the the cipher was sent in all capital letters with no punctuation marks.

The deciphered message reads as: "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 (paradise misspelled) 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 will be an easy one in paradice death."

The TV show mentioned is the "The Jim Dunbar Show", which a person claiming to be the killer had called two weeks before the cipher was sent.

Speaking to CNN, Oranchak, who had been working on the cipher since 2006, said: "It was incredible. It was a big shock, I never really thought we'd find anything because I had grown so used to failure.

"When I first started, I used to get excited when I would see some words come through -- they were like false positives, phantoms. I had grown used to that. It was a long shot... We didn't even really know if there was a message."

In its announcement, the FBI said that the 'Zodiac Killer' case "remains an ongoing investigation for the bureau's San Francisco office and its local law enforcement partners".

"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.

"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," it added.

The 'Zodiac Killer' remains one of the most famous unsolved cases in American history.