The Zodiac's first victim may have been Cheri Jo Bates, a student at Riverside, California. She was murdered outside the school library. Reports of a white male driving an old car was watching the scene. A month after the murder a letter was sent to the local newspaper and the same message was sent to the media, the police and the victim's father. The message read "Bates had to die. There will be more."
July 4, 1969 the Zodiac Killer attacked a couple, Mike Mageau and Darlene Ferrin, in Vallejo. Mike survived the shooting. The murderer sent letters to 3 area newspapers giving details of the scene. Every letter ended with a symbol that would be identified with the killer. A circle with two intersecting lines running through it.
Sending police untraceable codes