In another Zodiac case, a couple was slain at Twin Oak Ridge. What type of weapon was thought to be used?

Answer 1

On September 27, 1969, Bryan Hartnell and Cecelia Shepard were picnicking on the shores of Lake Berryessa, on a small island connected by a sand spit to Twin Oak Ridge. Zodiac, wearing a black executioner's type hood (but square on top like a paper bag) with clip-on sunglasses over the eyeholes and a biblike device on his chest that had a white cross-circle symbol on it, approached them with a gun; Hartnell thought it was a .45. He claimed to be an escaped convict from Deer Lodge, Montana, where he had killed a guard and stolen a car; he told his victims he needed their car and money to go to Mexico. He had brought pre-cut lengths of plastic clothesline and told Shepard to tie Hartnell up, then he tied her up. Zodiac checked Hartnell's bonds and found she tied him loosely, and so he tightened them. Hartnell initially thought it was only a weird robbery, but Zodiac drew a knife and stabbed them both, then hiked the 500 yards back up to Knoxville Road, drew his cross circle symbol on Hartnell's car door and wrote beneath it: Vallejo 12-20-68, 7-4-69, Sept 27-69-6:30 by knife.

At 7.40pm, Zodiac called Napa PD to report his crime, and officer David Slaight took the call; the phone booth was found minutes later at the Napa Car Wash, only a few blocks from the police station and 27 miles from the crime scene. Meanwhile, passing fisherman Ronald Fong discovered the victims and summoned help, and Hartnell and Shepard were taken to Queen of the Valley Hospital in Napa. Shepard lapsed into a coma and died two days later, but Hartnell survived to tell the bizarre story. (He went on to become a successful lawyer in Southern California.) The island (in the present day Oak Shores Recreation Area) on which the attack took place is even referred to locally as Zodiac Island; it has changed a lot over the years, since the three trees present at the time are now gone, and a picnic table sits right by the spot where Hartnell and Shepard were attacked. Sergeant Ken Narlow of Napa County Sheriff's Department investigated the stabbing; his best suspect was Rick Marshall, but there was not enough evidence for an arrest.