President Truman calls for thorough investigation into mine blast . Four missing miners are dead ; death toll in West Virginia coal mine disaster now at 29 . Most of the victims were working in an area where long wall construction was taking place .
President Obama calls for thorough investigation into mine blast . Four missing miners found dead ; death toll in West Virginia coal mine explosion now at 29 . Most of the victims were working in an area where long wall cutting was taking place .