MONTREAL - Quebec's anti-corruption unit raided 11 companies Wednesday morning in the latest round of sting operations.

One of the firms being investigated is Construction Frank Catania & Associates Inc.

Catania is working with the city of Montreal to build the Faubourg Contrecoeur housing development.

In 2010 the police squad raided the offices of Catania and the city of Montreal's development arm, SHDM, after a review of expenditures by independent accountant firms and the city's auditor general.

The owner of the firm, Paolo Catania, was fined in 2010 for making a donation of $3,800 to the provincial Liberal party in 2005, $800 over the limit.

Catania was fined a total of $1,635 for the offense.

Last week UPAC arrested 15 people, including construction magnate Tony Accurso and the mayor of Mascouche, Richard Marcotte, saying it was dismantling a network of collusion in the awarding of lucrative public contracts.

In all, 47 charges were brought against the 15 arrested, including fraud, corruption and abuse of confidence.