Five people, four men and a woman, are crouched next to a concrete wall at UC Berkeley (Sproul Plaza?). Four of them are wearing gas masks and helmets. At least three of them are holding one or more cameras. One man is filming with a movie camera. The camera rests on his shoulder as he looks through his gas mask into the viewfinder. In the foreground, a rock is sitting on the pavement. On the back of the photograph a description is written in blue ink. "Press pinned down by students throwing rocks." In April 1970, UC Berkeley students, as well as non-students, staged anti-war demonstrations over the course of several days. In order to show their opposition to the Vietnam war and the on-campus ROTC presence, protesters marched on California Hall, the location of the chancellor's office, and Callaghan Hall, location of the Naval ROTC's headquarters. Violence, including rock-throwing, erupted and police used tear gas to disperse the demonstrators. Members of the "Weathermen", a radical faction of the SDS (Students for a Democratic Society), were implicated in the organization of the protests.