QUEBEC - It was a rough start to the week for Jean Charest.

An online petition calling for his resignation nearly crashed Monday after thousands rushed to sign it.

By day's end, more than 20,000 people had put their name on it.

And that was only part of the day for the embattled Quebec premier.

Earlier, Quebec's union of municipalities joined the chorus of Quebecers who have been calling for a public inquiry into construction industry corruption.

Charest has seen his popularity nosedive over his refusal to call an inquiry into the matter.

Quebecers have been riveted for over a year by tales of well-connected construction companies, with ties to crime groups like the Mafia, rigging public contracts.

The petition, tabled by an opposition member and posted on the legislature's website, racked up about 40 new signatures per minute Monday.

It will be online for three more months.

Waves of people navigating to the website during the day appeared to put too much demand on the server, causing the page to freeze several times.

The person who penned it credited the massive interest to the population's discontent over how the government has been operating in recent months.

"It's clear to me that I'm not the only one who feels this way," said Steve Brosseau, whose petition was tabled by MNA Amir Khadir of the Quebec solidaire political party.

"People are fed up and they want to unite."

He hasn't set a final objective for his petition, but said he would be satisfied if it attracted 50,000 or 100,000 names.

Brosseau listed several reasons why he created the petition, including the allegations of government collusion with the construction industry, daycares and in the nomination of judges.

But Charest fought back Monday against his legion of detractors, a group that includes Action democratique du Quebec Leader Gerard Deltell.

Over the weekend, Deltell used organized-crime imagery to describe Charest -- calling him the "godfather" of the Liberal family.

Charest's lawyer sent Deltell a letter Monday threatening to launch a civil suit against him if he didn't retract his comments by 5 p.m. Tuesday.