The footage was shot by Eric Saarinen, who was on stage taking pictures of the crowd, and Baird Bryant, who climbed atop a bus. Saarinen was unaware of having caught the killing on film. This was discovered more than a week later when raw footage was screened in the New York offices of the Maysles Brothers. In the film sequence, lasting about two seconds, a two-meter (six foot) opening in the crowd appears, leaving Bredehoft in the center. Hunter enters the opening from the left. His hand rises toward the stage, and the silhouette of a revolver is clearly seen against Bredehoft's light-colored dress. Passaro is seen entering from the right and delivering two stabs with his knife as he parries Hunter's revolver and pushes him off-screen; the opening then closes around Bredehoft. Passaro was reported to have stabbed Hunter five times in the upper back, although only two stabs are visible in the footage. Witnesses also reported Hunter was stomped on by several Hells Angels while he was on the ground. The gun was recovered and turned over to police. Hunter's autopsy confirmed he was high on methamphetamine when he died. Passaro was arrested and tried for murder in the summer of 1971, but was acquitted after a jury viewed concert footage showing Hunter brandishing the revolver and concluded that Passaro had acted in self-defense. The Rolling Stones were aware of the skirmish, but not the stabbing ("You couldn't see anything, it was just another scuffle", Jagger tells David Maysles during film editing). But it soon became apparent they could see something of what had happened because the band stopped playing mid-song and Jagger was heard calling into his microphone, "We've really got someone hurt here... is there a doctor?". After a few minutes the band began playing again and eventually completed their set. Jagger told Maysles they all agreed that if they abandoned the show at that point, the crowd would have become even more unruly, perhaps degenerating into a full-scale riot. In 2003, the Alameda County Sheriff's Office initiated a two-year investigation into the possibility of a second Hells Angel having taken part in the stabbing. Finding insufficient support for this hypothesis, and reaffirming that Passaro acted alone, the office closed the case for good on May 25, 2005. The Altamont concert is often contrasted with the Woodstock festival that took place less than four months earlier. While Woodstock represented "peace and love", Altamont came to be viewed as the end of the hippie era and the "de facto" conclusion of late-1960s American youth culture: "Altamont became, whether fairly or not, a symbol for the death of the Woodstock Nation."