At least two people are dead, 12 are missing and 30 others are injured after two dams collapsed at a Brazilian iron ore mine.
Rescuers are searching for the missing under mud and debris from colossal floods that devastated a village.
Mine operator Samarco's chief executive officer said a tremor in the vicinity of the mine may have caused the dams to burst Thursday afternoon, but that it was too early to establish the exact cause. The company said one of the dead was a mine worker.
Samarco is a joint venture of BHP Billiton.
Firefighters who rescued 30 injured from the village of Bento Rodrigues put the toll at two dead and said the count was likely to rise as pouring rain slowed their search and mudslides knocked out roads and cell towers. The massive floods hit at least six villages.
Firefighters said they did not know if they would find all of those swept away by the wall of water released by the successive bursting of the two dams holding iron ore tailings and waste from the adjacent mine.
Television footage from the scene showed Bento Rodrigues, population 600, devastated by the fast-moving floods that tore off roofs, levelled trees and swept away cars. The floods extended as far as the town of Barra Longa, 80 km away. The town was partially underwater.
The head of emergency planning at Samarco told GloboNews of reports of seismic activity in the area in the hour leading up to the incident.
The collapse paralysed operations at the mine, a joint venture between Vale and BHP Billiton, the world's top iron ore miners, and raised fears of an expensive cleanup.
Shares of Vale were off 5.2 percent in Sao Paulo trading and BHP Billiton dropped 5.7 percent in London.