NEW YORK — A hazmat investigation at a luxury Brooklyn spa sent five people to hospital overnight, while emergency crews examined 15 others at the scene, authorities said.

Firefighters responded to a call about a certain type of odor in Spa of the world In McDonald Avenue in Midwood around 10:00 p.m. On Wednesday, it was determined that there had been an incident with hazardous materials in the basement of the building, although the nature of the incident was not immediately clear Thursday morning.

A total of 20 patients have been reported, the fire department (FDNY, for its acronym in English) said.

Five were taken to Coney Island Hospital in unknown condition. The other victims were treated and released at the scene.

The situation was reportedly under control shortly after 1 a.m. Thursday.

No further details were immediately available and World Spa could not immediately be reached for comment.

World Spa bills itself as “New York’s first and most diverse spa destination,” with 50,000 square feet of “urban baths” that guests can explore at their own pace, “enjoying new and culturally authentic and enjoying exquisite food and drink along the way.”

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