OAKLAND (CBS SF) — A third officer with the Oakland Police Department has been placed on administrative leave as part of an ongoing investigation into alleged misconduct involving officers and an underage girl.

After it was alleged that more than one officer had an ongoing sexual relationship with a police dispatcher’s underage daughter, two officers resigned and two others were placed on administrative leave in May.

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In a statement, police officials said the department was committed to transparency, however, the investigation requires confidentiality. “The Oakland Police Department holds all employees accountable for their actions on and off duty. The Oakland Police Department will not tolerate misconduct of any kind from its employees,” the statement read.

The possible misconduct was uncovered when the department’s internal affairs division investigated the suicide of Officer Brendan O’Brien last September.

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Police Chief Sean Whent announced his resignation on Thursday, although it was not immediately clear if his exit was related to the sexual misconduct investigation.

Whent will be temporarily replaced by BART Deputy Police Chief Ben Fairow, who will serve as interim police chief for up to six months while the city conducts a national search for a new permanent chief, according to city officials.

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