Zodiac Killer biography

The killer left a message on Hartnell's car door, which included the dates of the two earlier assaults and murders.

From the survivors, a sketch of the killer was created. He was described as a heavyset, white male in his late twenties or thirties with short brown hair and thick-rimmed glasses. During the attacks, he wore a large hood, like those worn by executioners.

Breaking from his usual pattern, the Zodiac Killer shot a taxi driver on October 11,

only a few weeks after the Hartnell-Shepard attack. Two days later, he wrote another letter taking credit for the murder and made threats about attacking a school bus and killing schoolchildren.

Still Unsolved

With the case remaining unsolved, it has been the subject of much discussion and speculation. Numerous books have been written on the Zodiac Killer with authors providing a bevy of possible suspects. Proposed suspects have included a follower of Charles Manson and the Unabomber Ted Kaczynski. Arthur Leigh Allen was a popular candidate for the Zodiac Killer, having been identified by Hartnell and Mageau as their attacker. But later DNA testing failed to link Allen to the crimes. In 2004, a representative from the San Francisco Police stated that "the case is being placed inactive."

In 2007, a producer for the feature film Zodiac (2007), about the notorious killer, discovered letters in police files that had not been tested for DNA, according to an article in Newsweek. Investigators hope that this new discovery may lead to a new break in the case.

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