Over 4,000 copper miners at the Cananea and La Caridad mines, as well as the Nacozari copper smelter and San Luis Potosi Zinc refinery have walked off their jobs for Grupo Mexico, the world’s fourth-largest copper producer, citing that the company failed to comply with health and education benefits and that failed to perform routine maintenance to ensure safety. The strike by the 250,000 member Mining and Metal Workers Union comes at the heel of a deadly gas explosion in Pasta de Conchos, which resulted in 65 miners being buried alive.