A Clayton County correctional officer who was fired after the sheriff said he used a racial epithet against an inmate had been terminated from a law enforcement job twice before, according to information obtained Monday by AJC.com

Officer Gregory Hubert Brown was placed on administrative leave Sept. 27 after referring to an inmate on suicide watch as a “crazy n-word," according to a separation letter from the sheriff’s office. He was officially terminated three days later on grounds that he neglected his duty and exhibited behavior unbecoming of an officer, the letter said.

Other inmates and another correctional officer witnessed the statement, the sheriff’s office said. No other details about the incident were released.

It’s the third time that Brown has been fired from a position in a correctional facility in the past 10 years, Georgia Peace Officer Standards and Training Council records show.

In December 2010, Brown was fired from the Coweta County Prison for “workplace violence” after a two-year stint as a corrections officer, according to a POST investigation case summary. In that summary, officials said Brown threatened and pushed another officer during a “heated verbal and physical encounter."

“Officer GB was asked to fill in incomplete information on an inmate count form by Officer AW,” the summary said. “Officer GB completed the information, but turned toward him and said ‘If you ever jump in my (expletive) again, I will tear your (expletive) head off of your shoulders.’”

Brown then walked “aggressively” toward the officer and pushed him with his chest, according to the summary.

A year later, he was hired by the Clayton County Sheriff’s Office as a jail officer, POST records show. Brown was fired from that position in 2012 after locking his colleagues in cells while inmates were inside, a POST case summary said. The case summary lists the official reason for termination as “unsatisfactory performance during his probationary work period."

According to the case summary, Brown was assigned to a control room within the Clayton County Jail. On three separate occasions, he locked sergeants inside cells while they were conducting checks. Brown also tried to open two segregation cell doors without being instructed to do so and used an emergency override to open two section doors “without proper justification.”

The summary also listed a series of reprimands for absenteeism, below-standard job performance, insubordination and failure to follow drug testing procedures while randomly testing inmates. Brown was also reprimanded for playing solitaire on a control room computer, the summary said.

The Clayton sheriff’s office rehired Brown in 2013.

— AJC data specialist Jennifer Peebles contributed to this article.