Rescue workers are seen after a explosion in the La Escondida mine in Sutatausa Feb 1, 2011. A methane gas explosion at the small, central Colombian coal mine on Tuesday killed five workers, officials said, the latest deadly mining blast to highlight the need for strong workplace safety measures. The explosion comes less than a week after another accident at a coal mine in northeast Colombia killed 21 miners and prompted the government to call for a mine safety review. [Photo/Agencies]