The fire at the Sunshine Mine near Kellogg is believed to be extinguished.

"All indications are that the actions taken over the weekend have been successful," said Monica Brisnehan, spokeswoman for Sunshine Silver Mines Corporation in an email Sunday. "Air sampling is indicating strong likelihood that the fire has been arrested. We are working with MSHA on a plan to accelerate the complete extinguishment of any remaining smoldering materials."

There are six workers from the U.S. Mine Safety and Health Administration on-site, working alongside mine employees.

Brisnehan said Monday that crews were underground, preparing to use a foam that will block all flow of oxygen, accelerating complete extinguishment of any embers.

A week after the fire began, there's no indication of what caused the incident. The blaze began on the 3100 Level, and the extent of damage is not yet known.

MSHA spokesperson Jesse Lawder said Monday that wooden timbers were burning from a rehabilitation project.

As of Saturday around noon, all indications were that it was no longer active at the original source. Crews installed a seal at the source of the fire, and three fire doors on 3100 Level and one on the 2700 Level were closed.

"We have historically and continue to have a good working relationship with MSHA and we believe that our shared experience and our cooperation will put forth the best plan of action," Brisnehan said.

Mine employees were notified of elevated carbon monoxide levels around 8 p.m. Tuesday, and the 12 contracted Redpath employees were immediately evacuated from underground. Brisnehan said MSHA was notified immediately, and ventilation systems were shut down.

There were 13 fires reported nationwide in underground metal/nonmetal mines or surface facilities at an underground mine in 2011.

Sunshine Silver Mines Corporation owns Silver Opportunity Partners, who operate the mine - that company currently employs 68, with 22 underground workers and 46 working in other areas.