Los Angeles County Sheriff Jim McDonnell has launched a comprehensive inquiry into secret deputy cliques and is looking into whether gangs that condone illicit behavior are operating within his ranks, he said Thursday.

McDonnell’s announcement at a meeting of the Sheriff Civilian Oversight Commission comes two weeks after allegations surfaced that as many as 20 deputies at the Compton Station have matching tattoos featuring a skeleton holding a rifle.

A Compton deputy recently admitted under oath that he was inked with the skull logo in June 2016, about two months before he was involved in a fatal shooting, The Times reported.

Watchdogs said the revelations were alarming given the department’s long history of secret societies that promoted excessive force and enforced a code of silence.

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