More than 20,000 students marched on Premier Jean Charest's Montreal office Thursday, in a massive protest against increases in tuition fees.

The march was part of a larger two-day strike being staged by an estimated 200,000 students across the province.

"Students are organizing and they'll be organizing throughout the winter," said Lex Gill, of the Concordia Student Union. "We'll be against these fee hikes until the Charest government freezes tuition."

Students from across Quebec converged on Berri square Thursday afternoon before marching to Charest's office at McGill College Avenue and Sherbooke Street.

The majority of the march was peaceful, but police did arrest two people after objects were allegedly thrown at officers. Two more arrests were made a short time later.

Earlier in the morning, students blocked entrances at Dawson College in downtown Montreal, allowing teachers and staff to enter through just one door.

That entrance was surrounded by a crowd of students holding signs denouncing the province's tuition plans. Classes at Dawson have been cancelled for the day.

The striking students have drawn support from a number of social activist organizations and unions.

Charest standing firm

Students have said the increase in tuition fees amounts to a declaration of war from Charest's government.

But the provincial government, which recently stood firm in a similar skirmish with unions, appears to be digging in its heels again.

Charest said he won't back down on the higher fees, which will increase by $325 per year from now until 2016.

That will bring annual tuition to $3,793, up from the current average of about $2,168. Charest said that, even with the increase, Quebec students would still be paying the lowest fees in Canada.

Quebec's tuition fees have been frozen for most of the last 40 years and the government said universities need the money.

Parti Québécois Leader Pauline Marois said the swift hikes put too heavy a burden on students.

With files from The Canadian Press