MONTREAL

Suburban Montreal mayor Richard Marcotte was arrested Friday in an alleged kickback scheme and police interrogated him for 10 hours upon his return from a Cuban vacation.

Provincial police have also offered protection to Claude Lachapelle, Marcotte's former chief of staff, who has gone into hiding after agreeing to blow the lid off the scam involving former Liberal organizers and construction entrepreneurs.

Detectives were waiting for Marcotte, mayor of Mascouche, Que., when a commercial jet landed at Trudeau Airport just after midnight.

He and his wife were taken to provincial police headquarters and his wife was released without charges in the middle of the night.

Marcotte, a former provincial Liberal candidate, was released late on Friday morning.

The 65-year-old faces several charges including fraud, conspiracy, bribery and embezzlement. Also charged is his close friend, Normand Trudel, whose construction firm received $40 million in contracts from Mascouche in the 2000s.

Marcotte and Trudel are among 15 people arrested this week in the first major roundup by Quebec's two-year-old anti-corruption squad that's looking into widespread rot in the construction industry.

Lachapelle could be the Crown's star witness.

Sources tell QMI Agency Lachapelle agreed to become a police informant and he is currently under tight surveillance at an undisclosed location.

Lachapelle provided enough information on the alleged kickbacks-for-contracts scheme to avoid being charged himself, sources said.

This, despite the fact Lachapelle's name is mentioned in more than two dozen indictments as an intermediary in alleged bribery transactions involving Mascouche contractors.

Two former Liberal organizers also face charges along with Tony Accurso, Quebec's most powerful construction magnate, who has spent years wining and dining politicians on his luxury yacht in the Caribbean.

Premier Jean Charest called for an inquiry after his own anti-corruption watchdog said the mob and biker gangs have infiltrated the construction industry.

The watchdog told the legislature last year that gangsters launder drug and extortion money through construction firms that hold public contracts.

Meanwhile, he said companies do their own money laundering, making illegal corporate donations to all political parties through employees who pass on "bonuses."

The suspects arrested Tuesday include men who have raised funds for all three of Quebec's main provincial parties.