Authorities quarantined nearly 20 emergency responders after they reported symptoms during a suspected overdose investigation.
MOUNTAINAIR, N.M. — Three people died and nearly 20 first responders were hospitalized after exposure to an unidentified substance at a home in rural New Mexico, where emergency crews responding to a suspected overdose began suffering symptoms including dizziness, nausea and vomiting, authorities said Thursday.
Investigators spent a second day trying to identify the substance that sickened sheriff’s deputies, EMTs and firefighters who entered the home Wednesday morning in Mountainair, a small town about 75 miles southeast of Albuquerque. Officials said the incident triggered a large hazmat response and forced emergency crews and hospital staff to isolate and monitor exposed patients while state police worked to secure the property. Authorities said there was no known threat to the broader public, but many details about the substance and how exposure occurred remained unclear.
New Mexico State Police said Torrance County sheriff’s deputies and emergency medical crews were first dispatched to the home near Hanlon Avenue after reports of an unconscious person. Responders arrived shortly before midday and found four people unresponsive at the property. One person was discovered outside the home, while others were located inside. Emergency crews performed CPR and administered emergency treatment at the scene before transporting survivors to hospitals in Albuquerque. Three of the four victims later died. Officials have not publicly released the identities of the dead while relatives are notified and autopsies continue.
Within minutes of entering the residence, several emergency responders began reporting symptoms including coughing, dizziness, headaches and vomiting, according to state police and local officials. Eighteen responders eventually required medical evaluation after potential exposure to the unidentified material. University of New Mexico Hospital confirmed that multiple patients underwent decontamination procedures before treatment. Two first responders were reported in serious condition late Wednesday, though some others were later released after observation. Mountainair Mayor Peter Nieto said local EMT crews were among those affected and described the situation as emotionally difficult for the small community. Investigators said early evidence suggested the substance may spread through contact rather than through the air, though testing was still underway Thursday. Officials also said carbon monoxide and natural gas exposure had been ruled out during the investigation.
The incident drew attention across New Mexico because of the unusually large number of emergency personnel affected during a single response call. Mountainair, a rural community with fewer than 1,000 residents, depends heavily on volunteer emergency crews and regional medical support. Local firefighters and EMTs described a chaotic scene as responders tried to assist victims while simultaneously recognizing that crew members themselves were becoming sick. Volunteer firefighter Antonette Alguire said she watched responders begin coughing and vomiting while patients were being treated near a helicopter landing zone. Authorities have not confirmed whether illegal narcotics or chemical contamination caused the deaths, though local officials acknowledged drugs were found at the property. New Mexico has continued to report some of the nation’s highest overdose death rates in recent years, particularly involving fentanyl and synthetic opioids, increasing concern among emergency personnel responding to overdose scenes.
Hazmat teams from Albuquerque Fire Rescue remained at the property Thursday as investigators collected samples and worked to identify the material involved. State police said the area surrounding the home had been secured and residents were asked to avoid the scene while testing continued. Investigators from multiple agencies, including environmental specialists and medical examiners, were expected to review toxicology results and evidence recovered from inside the residence. Authorities said no criminal charges had been filed as of Thursday afternoon, though the investigation remained active. Officials were also reviewing whether additional protective measures may be needed for emergency responders handling suspected overdose calls involving unknown substances. Autopsy findings and laboratory analysis are expected to play a major role in determining the official cause of death for the victims and identifying what triggered symptoms among responders.
Residents in Mountainair gathered around emergency staging areas and followed updates closely as ambulances, law enforcement vehicles and hazmat crews moved through the normally quiet community. Some local officials temporarily closed municipal offices while emergency personnel and town workers dealt with the aftermath of the incident. Mayor Nieto praised local responders for continuing to assist victims despite becoming ill themselves. “Time and time again, our entire town team rises to the occasion,” Nieto said in a public statement addressing residents. Hospital workers in Albuquerque also carried out decontamination procedures as exposed patients arrived from the scene. Authorities said several responders who initially feared severe contamination later improved after treatment and monitoring. Still, many unanswered questions remained Thursday about how the substance spread and why some individuals experienced stronger reactions than others.
State police said investigators expect additional laboratory results and medical findings in the coming days as authorities continue examining the Mountainair scene. Officials said the public is not believed to be in danger, but the investigation into the unidentified substance remains ongoing.
Author note: Last updated May 21, 2026.