Six people have been found dead at a dairy farm in Colorado after a suspected toxic gas incident, authorities have said.
Jolene Weiner, chief deputy coroner for Weld County, said all the victims were male and Hispanic.
Officers are “investigating these deaths as the possible consequence of gas exposure in a confined space”, she added.
The incident took place at Prospect Valley Dairy, located along a rural road near Keenesburg and around 35 miles northeast of Denver.
According to Sky’s US partner network NBC News, the local fire chief, Tom Beach, said firefighters responded to “a confined space rescue” at around 6pm on Thursday.
KUSA, a local affiliate of NBC News, reports that three others received hospital treatment. They have been released.
Weld County Sheriff’s Office spokeswoman Melissa Chesmore said “it looks like an accident,” and did not elaborate on the nature of the emergency or where the bodies were found.
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In an email to the Associated Press, US government spokesperson Chauntra Rideaux said the Occupational Safety and Health Administration was investigating.
Dairy Farmers of America added in a statement: “We are deeply saddened by this incident, and our thoughts and most sincere condolences go out to the friends and families of the deceased.”