FILE PHOTO: A logo of the Brazilian mining company Vale SA is seen in Brumadinho, Brazil January 29, 2019. REUTERS/Adriano Machado/File photo

(Reuters) – Prosecutors are planning to file criminal charges against Brazil’s miner Vale SA and its employees over the collapse of a mine-waste dam in January that killed hundreds of people, the Wall Street Journal reported, citing the lead investigator.

Investigators have gathered enough evidence to affirm that Vale employees involved in the mine operation knew the dam was unsafe, the report said, quoting Jose Adercio Leite Sampaio, the prosecutor heading the probe.

“At this point, we know that the operational side knew [that the dam was at risk of collapse], but did Vale’s directors know?” Sampaio said in an interview with the Journal.