Demonstrations erupted across Canada on Tuesday to support 14 anti-pipeline protesters who were arrested in northern British Columbia.

In Waterloo, dozens of protesters blocked traffic on King Street in Uptown Waterloo.

“This is unceded Indigenous territory that, as established by multiple Supreme Court decisions, is now being forcibly encroached upon,” said Rachel Thevenard, an organizer for the Waterloo demonstration.

Hundreds gathered around the country to support the Indigenous blockade over the construction of a natural gas pipeline.

The RCMP moved in to break up the camp, which some see as a violation of Indigenous rights.

Mounties say the arrests took place at the Gitdumt'en checkpoint on Morice West Forest Service Road for various offences, including alleged violations of an injunction order against the blockade.

Dozens of protesters delayed an appearance by Prime Minister Justin Trudeau where he was set to speak on Indigenous issues in Ottawa.

The company building the pipeline says it has signed agreements with all First Nations along the route for LNG Canada's $40-billion liquefied natural gas project in Kitimat, but demonstrators argue Wet'suwet'en house chiefs, who are hereditary rather than elected, have not given consent.

A news release issued Sunday on behalf of Grand Chief Stewart Phillip of the Union of B.C. Indian Chiefs says all five Wet'suwet'en clans, including the Gidimt'en, oppose the construction of oil and gas pipelines in their territory.

"The provincial and federal governments must revoke the permits for this project until the standards of free, prior and informed consent are met," Phillip says in the release.

Construction on the $6.2-billion pipeline, which is 670 kilometres long, is scheduled to begin this month.

B.C. Premier John Horgan said LNG Canada's decision would help an economically deprived region of the province and bring in an estimated $23 billion in provincial revenue.

Files on the circumstances surrounding the protest and both sides of the argument from The Canadian Press.