A Louisiana businessman claims he is the biological son of the infamous Zodiac Killer. In a book released earlier this week, Gary Stewart, who runs a cleaning company in Baton Rouge, explains that he discovered the identity of the elusive serial killer after a decade-long search to find his father, which led him to a man named Earl Van Best Jr. – the man Stewart claims is the killer.

Authorities in San Francisco, where the Zodiac Killer was most active, say they are not so sure about the claims. However, sketches of the serial killer and photographs of Earl Van Best Jr. do share similarities.

"Stewart's father had a criminal record in San Francisco ('forgeries, bad checks'), and there was a strong resemblance between his father's mug shot and the police sketch," HarperCollins publicist Tina Andreadid recently told New York Magazine.

"If you look at Gary's photo next to the sketch of the Zodiac (killer) next to his father's mug shot, you can see that there is very clearly more than just a passing resemblance," she said. "They look alike."

The Zodiac Killer is perhaps one of the most notorious serial killers in history, taking credit for his murders by contacting local newspapers and including ciphers in his messages with his supposed identity hidden inside.

The book states that one of the Zodiac Killer's ciphers contained the letters “EV BEST JR,” which Stewart says is a clear indication that his now deceased father was confessing to the crimes.

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