In January of 1937, in Botetourt County, Virginia, over the coruse of the month, several people were reported to have fallen ill due to apparent exposure to a certain toxic gas. The victims exhibited symptoms such as nausea and throat swelling. They reported that the gas had a sweet odor.
Years later, in September of 1944, there were again several reports of attacks with a sweet-smelling gas, this time in the town of Mattoon, Coles County, Illinois. Some even claimed to have seen an assailent or even several assailents fleeing the scene. There were several descriptions of the assailant, including a man dressed in dark clothing and "a woman dressed as a man" (keep in mind that back then men and women had much more distinctive styles of dress). One witness claimed to have seen a blue vapor during the attack coinciding with a wirring sound, possibly from a pesticide dispensor or something used to deploy the gas. Another family reported that their house had been barricaded from the outside to prevent escape. The attacks resulted in no permanent casualties and many doubt that the whole thing was anything more than a media-fueled case of mass-hysteria, or maybe the result of industrial pollution. Some believe that at most it was a series of copycat crimes. No suspect was ever apprehended, and as far as physical evidence goes, all they found was some discolored snow that was polutted with a compound that resembled a pesticide in terms of chemical composition (it also had a sucrous odor), a rag that was supposedly steeped in a chemical used for the attacks, and the barricade outside that one family's home. If these attacks did actually happen, the identity and number of the perpetrator or perpatrotors, as well as their motive, remains mysterious.