During a July 22 choir concert at St. Paul Parish in Cambridge, Massachusetts, eight children from the renowned French youth choir *Choeur d’Enfants d’Île-de-France* were hospitalized after showing “seizure-like” symptoms, according to the Cambridge Fire Department.

Witnesses reported a “strange odour” during the performance, which may have triggered the reactions. Acting Fire Chief Thomas Cahill said, “One student wasn’t actively seizing… that quickly escalated into seven other people.” All affected children, aged 11 to 13, were treated for non-life-threatening conditions and taken to hospitals. No prior health issues had been reported among them.

Roughly 70 people attended the concert. While some noticed an odd smell, authorities, including hazmat teams, found no hazardous substances. “The buildings were ventilated” and “results were negative,” the fire department confirmed on Facebook. Carbon monoxide was also ruled out.

Cahill described the event as “somewhat unusual,” adding, “It was a routine medical call that quickly escalated.” As of now, officials say, “We are not sure of what caused the reaction.”

All attendees were safely escorted from the scene with chaperones. The investigation remains open.