A computer attempting to crack cryptic letters left by the Zodiac killer has a very disturbing side-effect.
The Zodiac killer was one of the most infamous criminals of the 20th century, leaving behind a string of unsolved murders that spanned from 1968 to the early 1970s in Northern California.
During his reign of terror, in which he is believed to have killed five people but claims to have murdered 37, he sent mysterious coded messages to the media detailing his crimes, reports News.com.au.
The Zodiac killer was never caught and, in 2004, was officially declared inactive. His identity remains a mystery.
Despite this, an artificial intelligence software has been working non-stop to try and crack the serial killer's letters in the hopes of revealing who it is.