0644 GMT April 26, 2018
A spokesman for firefighters leading the rescue confirmed 30 injuries and at least two deaths, but said the count was likely to rise as the search advanced slowly after mudslides knocked out roads and cell towers, Reuters reported.
"In reality there are a lot more, but we can't confirm any more than that. We don't even know that we'll find everybody," said firefighter Adao Severino Junior in the nearby city of Mariana.
He said the local hospital was "saturated" and victims arriving by helicopter were being sent to nearby Ouro Preto.
The head of emergency planning at Samarco, the joint venture company that runs the mine, told GloboNews of reports of seismic activity in the area in the hour leading up to the incident. The company's press representatives could not confirm the reports.
The collapse paralyzed 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 4.3 percent in Sao Paulo trading and BHP Billiton dropped 7.6 percent in London.
Analysts at Clarksons Platou Securities said on Friday that the likelihood of a lengthy stoppage at the Germano mine, which accounts for about one-fifth of seaborne pellet market, could lift iron ore prices. Samarco produces 30 million tons per year of pellet, used to make steel.
Pellet prices have plunged by one-third this year to their lowest in six years amid a global glut and waning Chinese demand.