LOS ANGELES (AP) — After an internal investigation of its beleaguered jail system, the Los Angeles County Sheriff’s Department arrested one of its own deputies Thursday, saying he twice assaulted inmates then falsified reports about the incidents.

Deputy Jermaine Jackson, 35, who for five years has worked as a jailer in the Twin Towers Correctional Facility, was taken into custody without incident at about 4:30 p.m., the Sheriff’s Department said in a statement.

The district attorney has charged Jackson with four felony counts of assault under the color of authority and two misdemeanor counts of falsifying police reports.

One incident took place at the Compton courthouse lockup in December 2009, the other at the Twin Towers jail a year later, Sheriff Lee Baca’s spokesman Steve Whitmore said. In both incidents, Jackson is accused of assaulting inmates with his feet, which are considered a deadly weapon.

The arrest comes amid a broad investigation of the jail system — the nation’s largest with some 19,000 inmates — by the FBI after dozens of abuse allegations made public by the American Civil Liberties Union. And it comes three months after the independent Citizens’ Commission on Jail Violence released a report on its own investigation, which found a “persistent pattern of unnecessary and excessive force” and blamed Baca for a “failure of leadership.”

Whitmore said the internal investigation and Jackson’s arrest shows that Baca is taking the lead on reforming his jail system.

“The sheriff’s cleaning house,” Whitmore told The Associated Press by phone Thursday night. “Any deputy or any civilian that works in our jails that breaks the law, we are going to bring them to justice, that’s his promise.”

Jackson was being held on $100,000 bail in the same jail system in which he worked, and he has been relieved of duty without pay.

He has not entered a plea, and Whitmore did not know if he has hired an attorney.

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