News about the incident, which reportedly unfolded at a Shake Shack restaurant in lower Manhattan on Monday, has spread on social media, where it was confirmed by New York City’s largest police union in a tweet.

In a letter penned by the president of New York’s Police Benevolent Association, Patrick J. Lynch, the union told its members that the officers had a health scare after they decided to dine in at the local Shake Shack location on Broadway and Fulton Street while on duty as part of the protest detail.

As they sat sipping their drinks, they discovered “that a toxic substance, believed to be bleach, had been placed in their beverages,” Lynch wrote, noting that it only hit officers that something fishy was going on with their drinks after they had “already ingested a portion of their beverages.”

Alleging the drinks may have been tampered with, Lynch said that everyone on the force must stay vigilant, adding: “We cannot afford to let our guard down for even a moment.”

Shake Shack responded to the incident late on Monday night, stating the company was “horrified” by reports of the officers’ poisoning and that it is now “working with the police in their investigation” – which has yet to be formally announced.

The city’s second-largest police union the Detectives Endowment Association of the City of New York (DEA) has also thrown its own weight behind the allegation.

DEA President Paul DiGiacomo claimed that the officers were “intentionally poisoned by one or more workers at Shake Shack,” adding that all three officers were not seriously hurt in the incident and are recovering in hospital. He did not mince his words, accusing “pandering elected officials” of “emboldening” criminals who attack police officers “simply because of the uniform we wear.”

The PBA later said that several union members visited Bellevue Hospital to check on the sickened officers.

So far, no suspects have been publicly identified and no arrests have been made, but Shake Shack employees are being questioned, according to local media. A sample from one of the shakes was also sent to a lab for testing, but its results have not yet come back. ■