Authorities are trying to determine exactly what sort of accident occurred in a mine in southwestern Colorado that left two miners dead of carbon monoxide poisoning.
Ouray County officials say they've ruled out an explosion and mine collapse as the cause of the incident at the Revenue-Virginius mine Sunday morning.
Both the Montrose Daily Press and The Denver Post reported that investigators are looking at whether a blast on Saturday may have played a role. Federal mining regulators will be investigating.
The miners who died were identified as 34-year-old Nick Cappanno of Montrose and 59-year-old Rick Williams of Durango.
"I knew both of these individuals personally," said Rory Williams, the operations manager for Denver-based Star Mine LLC. "They were hard-working men. They were great men. They will be remembered indeed."
Nineteen other miners were taken to the hospital but only four were admitted. They were listed in fair condition.
The U.S. Mine Safety and Health Administration is at the accident site, which is about 270 miles southwest of Denver. The Denver Post said that the company has a permit to mine silver, gold and sulfides. About 100 miners work at the site, which will be closed until the end of the investigation, Williams said.
The last major mining disaster in Colorado occurred on April 15, 1981, when an explosion killed 15 people at the Mid-Continent Dutch Creek No. 1 Mine near Redstone. There have been eight mining deaths in the state since 2002, not including the two Sunday, according to the mine safety agency.
In 2011, a New Mexico contract worker died after being hurt at the West Elk Coal Mine in Somerset, in western Colorado. The agency found the 53-year-old slipped and fell from a beam at a tower construction site.
In 2012, a 25-year-old water truck driver died after losing control of his vehicle at Colowyo Mine in Moffat County.
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