Five men remain trapped underground after a cave-in at a coal mine in northern Mexico, officials of the Coahuila state government told Efe on Friday.
The accident took place around 10:15 a.m. at the VII mine outside the town of Progreso, state Public Safety Secretary Jorge Luis Moran Delgado said.
He said the mine is operated by the Mimosa unit of Minera del Norte, a subsidiary of steelmaker Altos Hornos de Mexico.
"There was no explosion," according to Moran, who said the initial reports point to a pocket of methane gas as having caused a "great landslide" of as much as 100 tons of earth and coal.
The mine's equipment and safety procedures allowed "the immediate and risk-free exit of 286 workers who were on the first shift," Mimosa management said in a statement.
Rescue squads "comprising 66 elements trained and equipped for the control of mining accidents" are searching for the five trapped men, the company said.
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. EFE