LOS ANGELES (CBS) — A group of Los Angeles County sheriff’s deputies will not be charged in an alleged of assault on three of their colleagues at a Christmas party after prosecutors declined to file charges, according to a report Wednesday.

The melee erupted at department party in Montebello in December 2010 and brought renewed focus upon the suspects, who are believed to belong to an overly-aggressive clique of deputies at the Men’s Central Jail in downtown L.A., the Los Angeles Times reported Wednesday.

According to a memo from the Los Angeles County district attorney’s office cited by The Times, charges were not filed against eight deputies in part because one of them who was alleging he was assaulted admitted he “struck the first blow,” which would “certainly raise the defense of self-defense.”

Prosecutors also found the statements of a female deputy who alleged she was punched in the chin to be unreliable.

The deputies described as the aggressors worked on the third floor of Men’s Central Jail, which had the highest number of use-of-force incidents compared to any other floor during a recent years-long span, according to The Times.

In March, the department moved to fire six deputies in what was called one of the largest terminations in connection with a single incident in Sheriff’s Department history.

Sheriff’s spokesman Steve Whitmore told The Times that the district attorney’s decision not to file charges does not affect the department’s ongoing internal investigation, which he said had been expanded.

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