The man accused of leaving a suspicious powdery substance at an NYC hotel is in police custody.

NYPD officials say a family checked into the Park Hyatt Hotel, located at 153 W 57th Street, on November 22, and checked out on Sunday around 10:30 a.m.

They believe that the family, who had five hotel room keys, may have dropped one of them while they were checking out.

Police say the suspect swiped into the 11th floor room several hours later around 8:30 p.m. and then left around 10:30 a.m. the next morning.

A housekeeper encountered a powdery substance when she went to clean the room, police say. She got sick and ended up at the hospital, where she is expected to survive.

FDNY personnel were initially called to the scene to check the room. The substance had already been swept up so there was no powder residue, but the original test of the remaining residue came back positive for traces of an explosive substance.

Authorities then evacuated the 11th floor as the NYPD tested multiple surfaces. All subsequent tests of the substance came back negative and the initial test was ruled a false positive.

The hotel is looking into why the room key card was not deactivated after the prior guest ended their stay.

Police say surveillance video captured footage of the suspect and they were able to identify him. The man has 16 previous arrests for low level crimes and was described as homeless.