By 1975, the cattle mutilation phenomenon had reached sufficient intensity to attract the attention of the Bureau of Alcohol, Tobacco and Firearms (ATF). Reports of mysterious helicopter activity near mutilation sites, coupled with suspected use of surgical instruments and possible chemical agents, prompted ATF involvement under its mandate to investigate potential federal weapons violations. ATF agents investigated several cases in the central United States, focusing on reports from Colorado, Kansas, and Nebraska where ranchers described black, unmarked helicopters in the vicinity of mutilated cattle.
The helicopter connection was taken seriously because the precision of the alleged mutilations and the absence of ground tracks near the carcasses suggested the perpetrators had arrived and departed by air. ATF investigations did not produce arrests or identify perpetrators, but the agency's involvement elevated the phenomenon from a local law enforcement matter to a federal concern. The ATF investigation coincided with similar inquiries by the FBI, state police agencies, and the Colorado Bureau of Investigation, making the mid-1970s the most intensively investigated period in cattle mutilation history.