The incident took place around 6:30 p.m., Wednesday, Nov. 6, when a white powdery substance, later identified as fentanyl, was "introduced" into the booking area, said Peekskill Police Lt. Jack Galusha.
Five officers and the arrestee were in the area at the time of the incident, he Galusha said.
Because of the dangerous nature of fentanyl, the Westchester County hazmat team was called and the booking area, as well as all present at the time, were decontaminated, he said.
No one was injured and after several hours operations returned to normal.
"Just a few granules of fentanyl can be deadly, so we needed to take all precautions," Galusha said.
Due to an ongoing investigation, Galusha declined to say how those present were exposed to the drug or the person who was under arrest.
Click here to follow Daily Voice Bronxville and receive free news updates.