Letters purported to be from a new "Zodiac Killer" that were sent to a number of media stations in upstate New York this week have the attention of federal investigators.
Law enforcement officials familiar with the case said the FBI is looking into the credibility of the letters -- which at this point in the investigation have not been connected to any violent crimes known to federal authorities.
The FBI office in Albany reached out to several upstate media stations Wednesday, after learning of the letters, and have asked to be kept in contact if more are sent out.
The Times Union, which first reported on the letters, said the letters came from someone claiming to be the "Chinese Zodiac Killer." The outlet did not receive one of the letters.
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But back in 1973, the Times Union did receive a letter from a person claiming to be the serial killer. The letter promised a murder in the Albany area, one that never came.
Part of the letter read: "YOU Were WRONG I AM NOT DEAD OR IN THE HOSPITAL I AM ALIVE AND WELL AND IM GOING TO START KILLING AGAIN Below is the NAME AND LOCATION OF MY NEXT VICTIM But you had Better hurry because I'm going to kill her August 10th at 5 P.M. when the shifts change. ALBANY is A nice Town."
In December of last year, the FBI confirmed amateur sleuths from around the world cracked a second coded letter mailed to a San Francisco newspaper by the serial killer in 1969.
The Zodiac killer terrorized Northern California communities and killed five people in the Bay Area in 1968 and 1969.