During an antiwar demonstration that spotlighted young Americans' disapproval of expanded participation in the Vietnam War, four students were killed and nine wounded in what became known as the Kent State Shootings, or the Kent State Massacre, on May 4, 1970. Previous to the shooting, large demonstrations were staged over four days that culminated in a confrontation between protesters and National Guard troops at Kent State University in Ohio. Tensions had risen after Kent State's ROTC* building was torched, and demonstrators vandalized property, smashed store windows and looted shops in town riots. Reacting to their entrapment on an athletic field, 70 National Guard troops wearing gas masks and provided with minimal riot-control training, advanced over the crest of Blanket Hill and fired between 61 and 67 shots at unarmed students. Although some of the students who were shot had been participating in the protests, others had simply been walking by or standing and observing. None of those wounded were shot at a range of less than 71 feet. The closest of those killed was almost a hundred yards away. Two of the students killed was simply going to class and one was a student member of ROTC. Following the Kent State shootings, many high schools, colleges, and universities were closed in response to the killings. No charges were ever brought against anyone for their role in the shootings.