A group of amateur Zodiac Killer crime sleuths planning to commemorate the 50th anniversary of the first murders have had to scrap their plans.
A threat to harm anyone who visits the original crime scene has people who follow the case closely feeling scared.
"It's the first thing I think of in the morning the last thing I think of at night," said Sandy Betts, Zodiac Killer crime sleuth. "I'm obsessed."
Betts has spent the past 50 years following the notorious Zodiac Killer case. She lived in Vallejo when the killings took place and even thought the killer was after her.
"I study it all the time," Betts said. "I go to all the task force meetings."
Betts and others planned to spend the upcoming 50th anniversary like they did the 40th: on a bus tour to the crime scenes and ending where the killing spree started along Lake Hermand Road in Solano County. That's where the Zodiac Killer shot and killed two teenagers in 1968.
But the tour organizer said he got repeated threats from a man -- threats he felt were so credible he canceled the tour.
"He was threatening to commit acts of violence on people show up to the crime scene in Vallejo on the 50th anniversary," said Tom Voigt with ZodiacKiller.com, an organizer of the tour. "I'm not willing to gamble with anyone's life and certainly having a bus full of people is a big responsibility."
Betts is making crosses that she planned to place at the scene. She is no longer going, but will to give them to somebody else who plans to go despite the threat.
"It's a shame because we want to show our respects and keep the case alive for the victims," Betts said. "We want this guy caught."