A couple hundred protesters showed up at the Fullerton Police Department to protest against the officers to beat a homeless man to death earlier this month.
The FBI confirmed it is reviewing the scuffle between Fullerton police and a 37-year-old Kelly Thomas suspected of possessing stolen goods who later died.
The Fullerton Police have placed one of the officers being investigated on administrative leave and taken the other five offers off street duty.
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"There is no way I believe all the good men and women of the Fullerton Police Department are bad," said Ron Thomas, father of the victim. "This is a group of rogue officers that did this and I encourage the good officers to come forward and report to the DA and FBI what they might know to clean the Fullerton name and clean their names."
Thomas confirmed to NBCLA that an attorney representing the city offered $900,000 to resolve the civil side of the case.
Thomas first disclosed the potential six-figure deal on the KFI-AM 640 "Jon and Ken Show." City attorneys have not yet confirmed that a formal offer was extended.
The FBI is looking into whether Kelly Thomas' civil rights were violated when Fullerton police struggled to arrest him earlier this month, Laura Eimiller of the FBI said.
The Orange County District Attorney's Office is also reviewing the circumstances of Thomas' death to see if any laws were violated. The FBI review will be a parallel investigation, Eimiller said.
"It's a separate investigation... it's independent of any other investigation," Eimiller said.
Eimiller declined to say what triggered the investigation or if anyone requested it. It was unclear how long the investigation would take.
If FBI agents conclude that Thomas' civil rights were violated then they will forward their findings to the U.S. Dept. of Justice, Eimiller said. It would be up to federal prosecutors to decide if charges should be filed, Eimiller said.
Fullerton police welcome the review, Fullerton police Sgt. Andrew Goodrich said.
"The Orange County District Attorney is investigating and we're cooperating with that investigation," Goodrich said. "As far as we're concerned we'll cooperate with whoever we have to. In the end, we're standing by our call for an independent third-party investigation." The autopsy of Kelly Thomas was inconclusive on the cause of death, and investigators were still waiting for toxicology reports, according to the Orange County Sheriff's Coroner's Office.
Thomas, who had a history of mental illness, struggled with police as they tried to arrest him about 8:30 p.m. July 5 at the Fullerton Transportation Center, 123 S. Pomona Ave. Thomas' family had him disconnected from life-support machines July 10, Goodrich said.
Six officers were trying to arrest Thomas on suspicion of possessing stolen goods, Goodrich said. They were called to the Metrolink station parking lot to investigate a complaint of a man trying to break into vehicles, Goodrich added.
The officers found Thomas at the lot and because he matched the description of the suspect they started talking to him, Goodrich said. They found evidence that he was in possession of stolen property from a burglary, he said.
However, when they tried to pat him down to arrest him, Thomas spun away and started fighting with the officers, Goodrich said.
"He wasn't the monster they are making him out to be, he wasn't a violent person," said Thomas' mother, Cathy. "He was loving, caring and gentile."
The protesters held signs of support and called for the police to take action against what some in the crowd labeled 'Police Brutality' on posters.
"I am overwhelmed at the amount of support we are getting today," Cathy Thomas said.