Authorities say the FBI has arrested four people in connection with New York City’s ongoing corruption probe, including a New York Police Department commander accused of accepting gifts that included time with a prostitute.

A criminal complaint alleges an unidentified real estate executive took James Grant, the commander of an Upper East Side Precinct, on a private jet for Super Bowl weekend in 2013 and arranged for a prostitute who stayed in Grant’s luxury hotel room. It says the executive is cooperating with the government.