2 Dead, 10 Hospitalized After Exposure to 'Unknown Contaminant' at N.Y. Senior Living Community

Two people died, 10 others were hospitalized and an emergency room was temporarily closed in New York after several individuals were exposed to an unknown substance at a senior living residential building.

The Syracuse Fire Department says crews arrived at the Brighton Towers apartment complex around 10 a.m. on Wednesday to find two people dead and one critically ill inside a unit on the sixth floor of Tower 1.

As they waited for the Medical Examiner to arrive, multiple Syracuse police officers reportedly began feeling sick, according to a press release from the fire department.

Officials soon determined that "some unknown contaminant was possibly responsible for the illness," and that the unit was potentially hazardous.

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Three police officers and a firefighter were transported to Upstate University Hospital, the SFD said. Shortly after they arrived, numerous hospital workers began feeling sick, as well.

As a result, the Emergency Department was closed for more than two hours "to manage the patients and prevent further exposures," according to the fire department.

Residents on the sixth floor of the impacted apartment building were temporarily evacuated "as a precautionary measure," but were allowed to return by 6 p.m. that evening.

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In total, nine first responders were hospitalized as a result of the incident, according to ABC affiliate WSYR-TV: four police officers, one firefighter, two EMTs, an Upstate Hospital nurse and an Upstate Hospital registration clerk.

The critically ill patient found inside the sixth-floor apartment was transported to a local hospital, and has since been discharged, according to the fire department.

The other nine individuals exposed to the substance have also been released from the hospital, according to WRVO Public Media, which noted that the resident was treated for an "altered mental status" before being released.

An investigation into Wednesday's incident is ongoing, according to the fire department.

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Officials suspect the mystery substance could be either fentanyl or xylazine, WSYR-TV reported.

But Onondaga County Executive Ryan McMahon said the evidence is "inconsistent with what we see with fentanyl overdoses," according to WRVO Public Media.

Additionally, 40 confirmed cases of xylazine overdoses were recorded in Syracuse over the weekend, per the report.