Tense confrontations between police and groups pushing for freer migration of refugees were seen in Quebec on Saturday.
Members of the group Solidarity Without Borders said their gathering at the Lacolle border was to welcome refugees and block a demonstration by a rival group.
One person was arrested and there was a brief scuffle between demonstrators and a right-wing commentator who was there to record the protest.
A counter-demonstration by groups denouncing the government's immigration policies was held later in the day, with members of the ultranationalist Storm Alliance in attendance.
An average of 50 people a day are believed to be bypassing official border crossings, using a loophole in the Safe Third Country Agreement, which might require them to be turned back to the U.S. if they entered Canada at a legal crossing.
The refugees have plenty of supporters on this side of the border, despite entering illegally.
"We know how desperate and scared they are to have come into this country this way. We just want to show them we are as welcoming as can be," said Holly Dressel of Bridges Not Borders.
However, some believe the migrants must enter Canada through official channels.
"Take the right route. Write your papers. Don't take a plane from an African country and then go through the States," urged protester M.J. Godon.
Discussions are underway with the U.S. about amending the Safe Third Country Agreement.
For now, Canada Borders Service Agency is sending more staff to Quebec and the government is building more shelters to accommodate the influx.
With a report from CTV National News Senior Political Correspondent Glen McGregor
