Vale SA and BHP Billiton Ltd, joint owners of the Samarco iron mine, are part of a group that includes 22 people and two other companies that stand accused of crimes related to a tailing dam that burst.

The burst unleashed a torrent of toxic mud that killed 19 people.

The court in the state of Minas Gerais suspended proceedings in July to consider claims from two Samarco executives who alleged that phone data, instant messages and emails were illegally collected outside of the period legally authorised.

The judge ruled certain material based on transcripts of corporate emails and chats to be invalid but that it did not impact the validity of telephone surveillance and other evidence, federal prosecutors said in a statement.

(Reporting by Marta Nogueira; Writing by Jake Spring; Editing by Lisa Shumaker)

Stocks treated in this article : BHP Billiton Plc, BHP Billiton Limited, Vale SA