At least two dams ruptured at a Brazilian open-pit mine on Thursday, sending a torrent of toxic sludge and wastewater pouring into a nearby village—submerging vehicles, sweeping away homes, and leaving over a dozen people feared dead.Located in the southeastern state of Minas Gerais, the mine is run by Samarco, a joint project between the Australian company BHP Billiton—the world\u0026#039;s biggest mining company—and the Brazilian company Vale—the largest iron ore producer. The structures that failed were tailings dams, which hold toxic chemicals and other waste from the mining process.The structural failure sent the waste pouring into the small town of Bento Rodrigues, located four miles downhill from the mine. Video footage shows homes and buildings ripped apart and submerged in mud, trees leveled, and a truck dangling upside down from a cliff-side.\u0022When I went outside there were already people running uphill saying the dam burst,\u0022 resident Joaquim Teofilo Dutra told the Associated Press. \u0022All I did was close my house and run to the top.\u0022As of Friday, the exact number of confirmed dead was unknown. A spokesperson for firefighters assisting with rescue efforts confirmed that at least two people were killed and 30 wounded. \u0022In reality there are a lot more, but we can\u0026#039;t confirm any more than that,\u0022 firefighter Adão Severino Junior in the city of Mariana told Reuters. \u0022We don\u0026#039;t even know that we\u0026#039;ll find everybody.\u0022According to some reports, up to 100 people are unaccounted for.Hundreds of survivors took shelter in a gymnasium near Mariana or at area hotels, as rescue efforts continued into Friday.Meanwhile, some have raised concerns that the the toxic sludge could contaminate the Gualaxo do Norte river that provides water to Belo Horizonte, a city of 2.5 million people.This is not the first massive and deadly dam rupture. A separate dam in northeastern Brazil burst in 2009, killing at least 24 people.Indigenous, poor, and working class communities across Brazil have raised repeated alarm about the harmful impact of large dams and mining projects on human and environmental health.