NEW YORK (CBSNewYork) — An NYPD deputy inspector has filed for retirement after being disciplined in the corruption probe into the department.

Deputy Inspector James Grant, head of the Upper East Side’s 19th Precinct, filed for retirement on Monday one month short of 20 years with the NYPD, police sources told CBS2.

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Grant was supposed to appear before the NYPD Internal Affairs Bureau to be questioned Monday, but instead, he showed up at One Police Plaza and put in his retirement papers, sources said. Grant did not appear for his interviews, sources said.

Police Commissioner Bill Bratton has 30 days to dispute Grant’s retirement and suspend him for retiring while under active investigation, sources said.

Grant was stripped of his gun and badge and transferred to working a desk in the medical division in the wake of the investigation.

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The NYPD probe has centered on two businessmen who have ties to de Blasio’s campaign. Jeremy Reichberg and Jona Rechnitz both served on de Blasio’s inaugural committee and either donated or raised money for him.

So far, at least nine police officials, including four deputy chiefs, have been transferred or stripped of their guns and badges as internal affairs detectives and FBI agents examine whether officers accepted gifts and trips from businessmen in exchange for police escorts, special parking privileges and other favors.

The probe has also involved an investigation of payoffs for gun licenses. Alex “Shaya” Lichtenstein of Brooklyn has been charged with bribing police to give him gun permits without doing background checks or providing justification for owning a gun.

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The investigation has also focused on fundraising efforts by Mayor de Blasio and his campaign team.