Seven bodies have been found and more than a hundred people remain missing after a dam operated by the mining giant Vale collapsed in the Brazilian state of Minas Gerais, releasing a wave of red iron ore waste and raising fears of widespread contamination... The incident comes less than four years after another tailings dam collapsed in Minas Gerais, killing 19 people in what was Brazil’s worst environmental disaster.... Vale’s chief executive, Fabio Schvartsman, told reporters on Friday that one dam containing iron ore waste, known as tailings, had failed and another overflowed. Brazil’s environment ministry had earlier said three dams were involved in the disaster. Schvartsman said around 300 staff we were working at the plant and 100 had been rescued....