Memory Alpha's riot timeline:
Early in the morning of September 1st, a fight between a guard and a dim sparked a riot, wherein the ghosts led by B.C. attacked the Sanctuary guards and quickly captured the Sanctuary Processing Center as well as the rest of the district. Armed with the weapons of the overpowered guards, the ghosts took six center employees hostage, including Vin, Calvera, and Lee. They were joined by "Gabriel Bell" and Michael Webb, who acted as the voice and face of the riot while dealing with police negotiator Detective Preston.
Chris Brynner, who owned Brynner Information Systems (which operated Channel 90 on the net), was convinced by Dax to break the law and to reconnect the Processing Center after the police cut it off. Reconnected on September 2nd, many Sanctuary residents (such as Henry Garcia) were able to tell their stories of imprisonment to the outside world. As a result, the American public became aware of the great injustice that had been hidden from them and further riots broke out in Sanctuaries across the US.
Despite protests from Detective Preston, the governor of California ordered National Guardsmen to retake the Sanctuary by force on September 3rd at 0500 hours. In the melee, hundreds of Sanctuary residents were killed, including B.C. and Michael Webb. "Gabriel Bell" was shot, protecting Vin and the other hostages (all of whom remained unharmed).
How dare you?! Lol.