What to know the mysterious deaths in New Mexico linked to unknown substance
May 21, 2026, 9:09 AM | Updated: 2:18 pm
New Mexico State Police respond to home in Mountainair, N.M., where authorities say several people died Wednesday, May 20, 2026, and more than a dozen first responders were exposed to an unknown substance and later treated at a hospital. (AP Photo/Savannah Peters)
Credit: AP Photo/Savannah Peters
(AP Photo/Savannah Peters)
MOUNTAINAIR, N.M. (AP) — Investigators in New Mexico are trying to identify a mysterious substance that may have contributed to the deaths of three people and led to more than a dozen first responders being briefly quarantined.
Authorities were called to a suspected drug overdose Wednesday and found four people who were unresponsive inside a home east of Albuquerque, in the rural town of Mountainair. Three of the people who were in the home died and the fourth was being treated at an Albuquerque hospital, police said.
Some first responders began coughing, vomiting and experiencing dizziness, authorities said.
The mayor said Thursday that officials were awaiting tests results.
Here’s what to know about deaths and the investigation.
It was not clear exactly how many first responders experienced symptoms.
Nearly two dozen people — mostly responders — were decontaminated and checked by medical workers, the University of New Mexico Hospital said. Hospital officials said three patients were being monitored Wednesday evening.
Antonette Alguire, a volunteer firefighter in Mountainair, said she saw some emergency medical technicians and firefighters coughing, and vomiting.
Hospital officials said most of the people evaluated had no symptoms and were discharged.
Mountainair Mayor Peter Nieto said he spotted drugs at the home that sits along a dirt road and pointed to that as a possible factor in the deaths. He did not say what type of drugs he thought they were.
He dismissed carbon monoxide or natural gas exposure as possible causes for the health issues that the first responders experienced.
New Mexico State Police spokesperson Wilson Silver said there was no threat to the public and that investigators do not believe the substance was airborne.
New Mexico had the fourth-highest rate of drug overdose deaths of any U.S. state in 2024, with 775 deaths, according to the most recent data available by the Centers for Disease Control and Prevention.
Residents around Mountainair, a town with less than 1,000 people, have voiced frustration about drug use in the community and elsewhere.
The mayor posted on social media that the town’s law enforcement officers and first responders work daily to protect the community and respond to difficult situations.
