The assassination of William McKinley occurred on September 6, 1901, inside the Temple of Music located on the grounds of the Pan-American Exposition in Buffalo, New York. President William McKinley was visiting the Exposition and was standing in a receiving line shaking hands with ordinary citizens when he was shot twice at close range with a .32 caliber revolver by Leon Czolgosz, an anarchist. One bullet grazed McKinley's sternum (breastbone) and another penetrated his stomach. A hastily assembled medical team, headed by a gynecological surgeon, operated immediately at the small Exposition hospital, but the second bullet could not be found. McKinley initially appeared to be recovering from his wounds, but took a turn for the worse on September 12, six days after the shooting. Over the course of the next two days his health quickly deteriorated and he died on September 14, 1901. At the autopsy, physicians found that the unrecovered bullet did not cause the death of the President through loss of blood and resultant shock. Instead, gangrene had developed along the path of the bullet, and McKinley died of septic shock due to bacterial infection.