NYPD: Officers sickened at Shake Shack were not intentionally poisoned despite allegation from union

NEW YORK — Shake Shack employees have been cleared of any criminality after three police officers were sickened by drinks from a Lower Manhattan location Monday night, according to the NYPD.

"After a thorough investigation by the NYPD's Manhattan South investigators, it has been determined that there was no criminality by Shake Shack's employees," NYPD Chief of Detectives Rodney Harrison tweeted just after 4 a.m. Tuesday.

According to police sources, it appeared a machine at the chain's Fulton Center location was improperly cleaned, resulting in the residue of a cleaning agent or bleach remaining inside when it was used to make beverages for the police officers.

The investigation came after three Bronx officers, assigned to a protest detail in Lower Manhattan, became ill after drinking beverages from the restaurant.

PBA President Pat Lynch said the police officers were hospitalized but were expected to be okay.

The Detectives' Endowment Association initially claimed on Twitter Monday night that officers were "intentionally poisoned" by workers at the Shake Shack location, a claim the NYPD did not corroborate early Tuesday.

"Our team is working hard to get the full picture," Shake Shack tweeted Tuesday morning. "In the meantime, we're relieved to hear the officers are all okay."

While ongoing protests in New York against police brutality have largely been peaceful, the NYPD says more than 350 officers have been injured since demonstrations began in early June.

Among those injured was Sgt. William Maher, who was struck by an SUV and was hospitalized for several days, police said.

This story was originally published by Aliza Chasan, Anthony DiLorenzo and Mark Sundstrom on WPIX in New York.