Brazil's Batista oil firm OGX in bankruptcy
30 October 2013 Last updated at 23:30 GMT
OGX, the Brazilian oil and gas company controlled by the billionaire Eike Batista, has filed for bankruptcy protection in a Rio de Janeiro court.
The move came after OGX said long-running talks with creditors to restructure some of its $5.1bn (£3.2bn) debt failed on Tuesday.
The company has struggled with large debt and a crisis in investor confidence.
The BBC's Wyre Davies reports from Rio de Janeiro