In Wyoming in the 1880s, the open range was controlled by cattle kings, and powerful stockgrowers often blamed rustlers for cattle losses while also fearing the influx of small operators using government land grants that threatened the open range. Stock detectives were hired to protect large herds and intimidate would-be ranchers, small ranchers were labeled rustlers, and cowboys suspected of rustling were blackballed and denied work with the big outfits. In 1886-87, a devastating drought followed by the worst winter on record exposed poor management practices and caused financial collapse for many large operations. In a final act of desperation, some radical members of the Wyoming Stock Growers Association planned an invasion of Johnson County for April of 1892 using hired gunmen. After a daylong shoot-out at the KC Ranch in which Nick Ray and Nate Champion were killed, the invaders headed for Buffalo, but after being warned about armed resistance there, the self-proclaimed regulators holed up at the TA Ranch, then owned by sympathizer Dr. William Harris. Surrounded and besieged by a civilian posse for three days, the invaders surrendered to federal troops from nearby Ft. McKinney on April 13, were eventually released, and had all charges against them dismissed. The major confrontation of the invasion marked the end of the open range cattle era.