The author alluded to killing more than one person when he used the word "slaves" along with "They were killed by a freeway", suggesting his attack claimed at least two victims.
Previous confirmed Zodiac attacks had involved the killer approaching the victims cars at some point, either before or after the attack, and in particular during the Zodiac Killer's first two crimes at Lake Herman Road and Blue Rock Springs Park. So, with the mention of 'freeway' in this letter, it obviously suggests we should be looking for a scene bearing these hallmarks.
As this letter was postmarked May 6th 1986, he would have almost certainly been referring to this crime, because he stated in the letter approximately "two weeks ago", hencesometime in the latter third of April 1986. But what is interesting, is the author of the letter stated "The Blue Meannies almost caught me". Exactly two weeks prior to May 6th, on April 22nd 1986, Koy Ien Saechao (48) and Choy Fow Saelee (40), a Laotian couple were brutally gunned down by the interchange of Highway 99 and Interstate 5 in Sacramento, California after they had pulled over to take a break. Koy Ien Saechao and Choy Fow Saelee were traveling back on the three-hour journey to their residence in Dorman Road, Yuba City after visiting their son in a Merced CA hospital, situated in the area of the San Joaquin Valley of Northern California. They were only 45 to 50 minutes from home when it was believed they had opted to take a rest on the roadside edge, near the interchange of Highway 99 and I-5 Sacramento - and unfortunately for them a ruthless killer was in the vicinity. However, without knowing the exact dynamics of the crime, it is equally plausible they were ushered to the side of the highway on a ruse, similar to the Modesto abduction of Kathleen Johns.
In 2001 Devon Stuart Olson confessed to the murder of the Yuba couple, apparently attempting to provide investigators with details of the crime, however, little connected him to the crime and he was never charged. He also laid claim to another 10 murders, his connections to which were roundly discredited by law enforcement. Despite several terms in prison for other offences he was paroled in 1998 and has never been heard from again. This is a debatable Zodiac letter as it is a Zodiac crime, but it is without much doubt, the author of the 1986 letter is describing the senseless slaying of Koy Ien Saechao and Choy Fow Saelee on Highway 99.
FOLLOW UP ARTICLE - MURDER BY THE FREEWAY