Brown told Eyewitness News in an exclusive interview that he did inform on the sheriff's department after witnessing alleged corruption, beatings and other wrongdoing.
Brown was in jail for a 2009 crime spree that included a shooting at Farmer Boys restaurant in downtown Los Angeles and robberies at El Pollo Loco, Rite Aid, Denny's, Burger King and at least three banks.
Brown was awaiting trial at Men's Central Jail when he was recruited by the FBI to inform on potential abuse and corruption in Los Angeles County jails.
Brown convinced now-fired Deputy Gilbert Michel to smuggle a cellphone into jail for him. Michel bought the phone from Brown's supposed "associate" on the outside, not knowing that associate was an undercover FBI agent, one of Brown's FBI handlers.
Michel accepted $1,500 from the undercover FBI agent and was promised $20,000 more by Brown. But on Aug. 8, 2011, the contraband cellphone was discovered. Sheriff's department investigators quickly learned that Brown had been repeatedly calling the FBI from jail.
"They brought me in and they asked me, where did I get the phone? And they asked me, who am I with? Am I with the FBI?" Brown told Eyewitness News during a phone interview.
Brown said he was "hidden" and "kidnapped" by a team of sheriff's department employees, seven of whom were indicted on Monday.
Brown said he was moved from place to place and his name was repeatedly changed. He was interrogated for hours on end about what he had told the FBI.
"They asked me a lot of questions. They asked me a whole bunch of questions -- the phone, the crooked officers, so on and so forth," said Brown.
Sources tell Eyewitness News that computer records were changed and records were destroyed to keep the FBI away from their own informant.
"The indictment alleges that the deputies altered records to make it appear that the informant had been released but they really only rebooked him into custody under a different name and then moved him to an isolated corner of the detention system," said U.S. Attorney Andre Birotte.
Eyewitness News obtained internal emails referring to the operation to move Brown around as "Operation Pandora's Box."
Brown was eventually rebooked into Men's Central Jail. That's when Deputy Gerard Smith, one of those indicted Monday, sent an email saying, "Over the past few weeks you have helped out tremendously with the safeguarding of inmate Anthony Brown. You have done so without asking too many questions and prying into the investigation at hand. I am both proud and thankful to have each and every one of you to rely on, in a time of need."
Two lieutenants, two sergeants and three deputies involved in moving Brown around were indicted by the U.S. Attorney's Office.
Brown, meanwhile, is in state prison, serving 423 years to life for the armed robberies.
Have a tip? Email the producer of this investigation: Lisa.Bartley@abc.com