A rescue team found and recovered the bodies of six workers trapped inside a coal mine in the northern Mexican state of Coahuila, officials told Efe.
State Public Safety Secretary Jorge Luis Moran Delgado said initial reports indicated five miners were trapped but that that number later rose to six, while another worker, Armando Robles Piña, was rescued alive.
Coahuila's deputy emergency management chief, Francisco Martinez, also confirmed to Efe Friday afternoon that a rescue crew had recovered the bodies of the six miners who perished in the accident.
"The most recent report is that we now have the bodies of the six people and all that's left is to officially identify them," the official said.
Martinez said some 75 rescue workers using special equipment took part in the search operation at the mine, which is located in the town of San Juan Sabinas and operated by the Mimosa unit of Minera del Norte, a subsidiary of steelmaker Altos Hornos de Mexico.
Moran said an investigation will now be launched "to determine the causes of this fatal accident."
He said the accident occurred at a large coal mine being "professionally" developed by a company "that normally has all the permits and (complies with all) safety standards."
"Unfortunately, accidents happen in all situations," Moran said, adding that Mimosa "has been fully cooperating with authorities" and contributed to the search-and-rescue effort.
In a statement, Mimosa said the one worker rescued alive had "only bruises" and was taken to a hospital for treatment.
It added that a pocket of methane gas caused a giant landslide of "approximately 100 tons of coal" and that "proper functioning of the ventilation system prevented the gas from igniting and exploding, while the automatic control systems inside the unit instantly suspended the operation."
The mine's equipment allowed "the immediate and risk-free exit of 285 workers who were on the first shift," Mimosa said.
The Labor Ministry, for its part, said that once the rescue efforts have concluded it will conduct a "special inspection of safety and hygiene conditions to identify possible violations of (mining) regulations."
The ministry said it has instructed the federal prosecutor for the defense of labor, "who is already in the region," to provide free legal counseling and representation to the workers and their families.
Seven men were killed last week in an explosion at a coal mine in the nearby town of Muzquiz, Coahuila.
Coahuila is home to numerous coal mines, many of which fall short of official safety standards.
A February 2006 gas explosion at the Pasta de Conchos coal mine in San Juan de Sabinas, Coahuila, killed 65 men. Only two of the bodies were ever recovered.