COMMERCE CITY - Police are working to pinpoint the source of a mysterious vapor cloud that made a group of senior citizens sick on Sunday night.
9NEWS received a newstip that half a dozen seniors became ill while standing outside the Commerce City Recreation Center at 60th and Monaco.
The senior citizens were about to board a bus at the rec center to listen to children sing Christmas carols.
The incident is puzzling for police and alarming for the seniors who got sick, including a 70-year-old grandmother named Mary who asked 9NEWS not to show her face or give her last name citing safety concerns.
She spoke exclusively to 9NEWS about the ordeal.
"It was horrible! Just plain horrible," Mary said."We were just all ready to go listen to the children sing."
As the group walked out the doors of the rec center, they walked into what police describe as an invisible vapor cloud.
"That's when I swallowed whatever it was and immediately I started choking, coughing, vomiting," Mary said.
Commerce City is an industrial area but police say only homes and restaurants are in the immediate vicinity of the rec center so there is no obvious source of the vapor cloud.
Paramedics treated Mary and the others on scene, but she's still feeling sick.
"My nose feels like its burning. I'm still headachy, light headed," Mary said.
Mary may have to go to hospital if her symptoms don't improve.
Commerce City police commander Dennis Moon says the vapor cloud was gone by the time first responders arrived.
"This is very unusual. It's not very common that unknown vapors cause something," Moon said. "We want to find out what caused it, get the information to the people who are affected, and if anything done was criminal, to prosecute that."
Mary says the worst part is the unknown.
"It's scary," she said. "I want to know what it was. I hope and pray it doesn't happen to anybody else."
Commerce City police are asking anyone with information to call (303) 287-2844.
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