LOS ANGELES — In one video, the sound of a Taser going off is followed by a man screaming in pain. In another, footage from a security camera on a public bus, riders describe police officers beating a man to death in graphic terms.

"They beat him up, and then all the cops came and they hogtied him, and he was like, 'Please God, please Dad!' " one said.

The death of Kelly Thomas, a mentally ill homeless man, at the hands of members of the Fullerton police department has set off a furor in the Orange County community, amid allegations that police used excessive force to try to quiet Thomas.

At a City Council meeting this week, hundreds of angry residents demanded the resignation of the police chief and vowed to recall several council members.

Police have not offered a clear report of what happened July 5 when they responded to reports of a man trying to break into cars, and made contact with Thomas, according to Sgt. Andrew Goodrich, a police spokesman.

At the end of the altercation, Thomas, 37, lay unconscious and severely beaten and was taken to a hospital. Pictures of him at the hospital show his face swollen, bruised and bloody. He was taken off life support and died five days later.

Photos of Thomas and videos of the beating and its aftermath were circulated on the Internet by his father Ron Thomas, and outrage grew.

Six officers involved in the incident have been placed on paid administrative leave. The FBI also has opened its own investigation.

Thomas aspired to be a wildland firefighter until he began showing symptoms of schizophrenia in his early 20s, his father said.

The disease robbed him of his ambitions and left him wandering the streets when he wasn't in jail for violations from public urination to assault with a deadly weapon.