Quebec's anti-corruption squad began raiding the offices of the BPR engineering firm on Thursday morning.
About 30 officers from UPAC are investigating the firm's Montreal offices, while another 30 are working in Quebec City. They are searching for evidence in connection with its links to the Montreal water meter scandal.
Several past and present employees testified during the Charbonneau commission about how they invited provincial and municipal politicians on fishing trips in order to win influence and contracts, and the extensive donations that were often illegally made to all major political parties.
BPR-Tetratech has been investigated before in connection with alleged corruption and collusion in awarding contracts in Mascouche, Boisbriand, and other small towns in Quebec.
Earlier this year four BPR employees were found guilty of the illegal lobbying of municipal politicians in Riviere du Loup.