The desecration of a war memorial in Ottawa and harassment of some city officials and NGO volunteers sparked an angry response after thousands of demonstrators brought Canada's capital to a standstill for a second day on Sunday during protests against federal vaccine mandates.
The police said they had launched “several investigations” in response.
A “Freedom Convoy” of lorries was joined by other sympathetic lorry drivers who blocked a border motorway into the US.
Images of Nazi flags, along with footage of vehicles parked on the national war memorial with beer-drinking protesters dancing on the Tomb of the Unknown Soldier, dealt a blow to the convoy’s calls for peaceful protest.
“I am sickened to see protesters dance on the Tomb of the Unknown Soldier and desecrate the National War Memorial,” Wayne Eyre, the country's chief of the defence staff, said on Twitter.
“Generations of Canadians have fought and died for our rights, including free speech, but not this. Those involved should hang their heads in shame.”
The chaos clogged the capital's city centre near Parliament throughout the weekend and protesters speaking on a makeshift stage said they did not intend to leave anytime soon.
Canada’s legislature has been on a winter break since the middle of December but is scheduled to resume sitting on Monday.
“This afternoon, a large presence of police continues throughout the downtown core and the movement of protesters and lorries continues to be managed,” Ottawa's police said.
“These high-risk situations were de-escalated and resolved with no arrests,” the authorities said.
However, “police resources are fully stretched” in dealing with the obstruction, which appeared to involve hundreds of lorry drivers.
The protest began last week in western Canada, where hundreds of lorry drivers organised a convoy to drive from Vancouver to the Canadian capital to demonstrate against coronavirus-related restrictions, particularly a recent vaccination requirement for lorry drivers crossing the long US-Canada border.
Lorries began arriving in Ottawa on Friday in several convoys and were joined by thousands of other anti-vaccination protesters.
In solidarity with the convergence on Ottawa, lorry drivers on Sunday staged what police described as a “complete blockage” of Motorway 4 in western Canada's Alberta province along the US border.
The road is a major artery for commercial goods between the two nations.
“As of right now … the port of entry remains open technically speaking. However, nobody would be able to get to them except on foot,” Curtis Peters, a spokesman for the Royal Canadian Mounted Police in Alberta, told AFP. He said about 100 lorries were blocking the road.
Barricades were installed on Sunday to block vehicle access to the area around the war memorial, after several illegally parked vehicles were towed away.
A soup kitchen near Parliament said its staff were intimidated by some demonstrators into giving them free food. A statue of Terry Fox, an amputee who became famous for attempting a cross-country trek to raise money for cancer research, was draped with protest propaganda.
Liquor stores in Ottawa's city centre were closed early on Saturday and remained shut on Sunday. Other local businesses were swamped by demonstrators defying mask mandates, and a large shopping mall in the city centre closed after protesters refused to follow Covid-19 regulations.
With protesters gathering, Prime Minister Justin Trudeau and his family were moved to an undisclosed location in Ottawa on Saturday, Canadian media reported.
The Canadian Trucking Alliance, a major industry group, said the vast majority of the country's lorry drivers are vaccinated. It has “strongly disapproved” of the disruption in Ottawa.