A gas tank and road flare were found underneath the pickup truck belonging to FTQ-Construction president Yves Mercure on Wednesday night in Le Gardeur, Que. (CBC)A special Quebec police squad has been called in to investigate after a pickup truck belonging to the president of the construction wing of the Quebec Federation of Labour was set on fire Wednesday night.

The incident happened outside the home of FTQ-Construction president Yves Mercure in Le Gardeur, east of Montreal. Mercure, who was home at the time, was alerted to the fire by police around 11 p.m.

A tank of gas and a road flare were found underneath the pickup, the CBC's French language network reported.

On Thursday, local police called in Operation Hammer, the special squad investigating allegations of collusion and corruption in the construction industry, to take over the investigation.

Mercure said the fire doesn't worry him.

"Why would I be afraid?" he said to Radio-Canada in a brief interview outside his home. "It's only material [damage].

"No one was injured, that is what is important."

The union leader said he has no idea who might be responsible for the fire.

"I have a job to do and I will continue to do it," he said.

Former union leader in court

The Quebec union has been embroiled in controversy.

The union's former director, Jocelyn Dupuis, made an appearance at the Montreal courthouse Wednesday morning. Dupuis is facing fraud charges in connection with expenses claimed from Quebec's biggest union.FTQ-Construction president Yves Mercure says he has no idea who could have been behind the fire. .(CBC)

Dupuis chose to be tried before a judge and jury. He will return to court for a preliminary hearing in mid-February.

He also asked the court to give him back his passport. The Quebec Court judge agreed Dupuis can travel outside the country but must notify police in advance.

FTQ-Construction members have also faced allegations of intimidation and threats at construction sites in the province's North Shore region.

On Tuesday, the union announced its assistant director, Alain Pigeon, was leaving his job as a result of a mutual agreement.

Two weeks earlier, the union's director, Richard Goyette, who had been on sick leave, announced he would not return to his position.

The province created Operation Hammer in October. The government has continued to reject calls from opposition parties for a public inquiry into alleged corruption in the construction industry, as well as concerns about political party financing practices.