A dam holding back waste water from an iron ore mine in Brazil that is owned by Vale and BHP Billiton burst on Thursday, devastating a nearby town with mudslides and leaving officials in the remote region scrambling to assess casualties. The mining company Samarco, a joint venture between top iron ore miners Brazil's Vale and Australia's BHP, said in a statement it had not yet determined why the dam burst or the extent of the disaster at its Germano mine near the town of Mariana in Minas Gerais, south eastern Brazil.
