(Updates with documents)
By Marta Nogueira
SAO PAULO, Sept 20 (Reuters) - Brazilian federal police formally accused Vale SA, auditor TÜV SÜD and 13 of their employees of fraud in relation to a January dam collapse which killed nearly 250 people, according to a document seen by Reuters.
Federal police said both companies worked with falsified documents attesting to the dam's stability in Brumadinho, in the southeastern state of Minas Gerais, a source with knowledge of the matter said.
As a consequence, the dam continued to operate normally, although it was below safety requirements.
Vale said in a statement it was aware of the police investigation, but would not comment further until it has more details. TÜV SÜD declined to comment.
It was not clear whether employees under accusation are still working for Vale and TÜV SÜD.
Brazilian news website G1 first reported on the police accusation. (Reporting by Marta Nogueira; Writing by Carolina Mandl; Editing by Chris Reese and David Gregorio)
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