Investigators with Operation Hammer have arrested seven people including the former mayor of Boisbriand, Que., Sylvie St-Jean, in connection with a corruption scandal that allegedly spanned between 2003 and 2009.

The suspects, who face charges of fraud, bribery, conspiracy and extortion, were picked up and released on Thursday with a promise to appear in court.

Sgt. Guy Lapointe said the alleged scheme involved construction companies bribing elected officials and bureaucrats with trips and cash incentives in exchange for big municipal contracts.

"Certain entrepreneurs or businessmen would give gifts, certain advantages or contribute illegally to election campaigns in return for advantages towards the attribution of municipal contracts," said Lapointe.

Saint-Jean herself faces fraud, conspiracy and influence peddling charges.

Special squad created

Opération Marteau, French for Operation Hammer, is a specialized squad which was created in 2009 to investigate allegations of corruption and collusion in Quebec's construction industry.

The move followed a series of investigative reports by the Radio-Canada program Enquête — including one looking at Infrabec's owner, Lino Zambito, who was among those arrested Thursday.

The report alleged that Zambito colluded with Saint-Jean to discourage her potential rivals from running in the city's Nov. 1 municipal election in 2009.

The program obtained a recording of Zambito trying to persuade opposition councillors Patrick Thiffaut and Marlene Cordato to drop out of the race.

Shortly after Cordato refused, two men visited her home and assaulted her husband.

Zambito, whose company received more than half of the municipal contracts in Boisbriand between 2004 and 2009, admitted to Radio-Canada that he tried to convince the councillors to drop out. He said wanted to save taxpayers the cost of an election.

At the time, Saint-Jean denied there had been any favouritism in the awarding of city contracts.

Cordato was elected mayor of Boisbriand in 2009.

The suspects will be arraigned on Apr. 19, at the courthouse in Saint-Jérôme, Que.