On August 1, 1969, the S.F. Chronicle, S.F. Examiner, and Vallejo Times Herald received identical handwritten letters from a person who claimed to have killed the victims. He included specific facts that were information that only the killer would know. The letter was signed with a mark with a circle and a cross through. The letters also included 3 different codes that the killer wanted the newspaper to print. He threatened to kill more people if it was not printed.
On August 4, 1969, another letter was received. This letter was the first time where the killer referred himself as the "Zodiac".
The killer later writes that he encountered the two officers on the scene of the murder of Paul Stine.
The killer also says that he planted fake fingerprints to throw the police off his trail.
2 days later S.F. Chronicle gets a letter claiming the responsibility of the murder of the taxi driver. Paul Stine's bloody shirt was also included in the letter.
More horrifyingly, the letter also includes plans to kill school children. Diagrams of bombs were also sent to S.F. Chronicle.
The killer also says that he planted fake fingerprints to throw the police off his trail.
2 days later S.F. Chronicle gets a letter claiming the responsibility of the murder of the taxi driver. Paul Stine's bloody shirt was also included in the letter.
More horrifyingly, the letter also includes plans to kill school children. Diagrams of bombs were also sent to S.F. Chronicle.
On April 20, 1970, a letter to the S.F. Chronicle included a piece of evidence from a letter wrote "My name is _____".
In 1974, the Zodiac Killer sent his last letter about his view on "The Exorcist" and the number of people he killed.