Via Rail says it is cancelling all train service on the Montreal-Toronto and Toronto-Ottawa routes until the end of Thursday due to an anti-pipeline blockade near Belleville, Ont.

Spokesperson Marie-Anna Murat said on Tuesday that Via service is cancelled "in view of the current uncertainty."

Via has cancelled 157 trains since the blockade began on Thursday, affecting at least 24,500 passengers.

It's estimated service will resume "at least 36 hours from the time the line is cleared," Murat said in an email. She said "heavy rail congestion" has been building since last Friday east and west of the blockade on CN tracks in eastern Ontario.

The blockade by the Mohawks of Tyendinaga , along one of Canada's busiest rail corridors, comes in response to the RCMP's recent enforcing of a court order in B.C. on Wet'suwet'en camps built to block construction of the Coastal GasLink pipeline.

The Mohawks have said they won't leave until the RCMP have left Wet'suwet'en territory. The RCMP have finished dismantling the Wet'suwet'en camps, but remain in the territory to ensure compliance with the court order.

A First Nations protester stands in front of a transport at the blockade on Tuesday. (Lars Hagberg/The Canadian Press)

Ontario Provincial Police, however, said on Tuesday they are preparing to end the blockade.

Calling the situation "dire," OPP officers told demonstrators to clear the area or face a raid and arrests. The demonstrators who met the officers said they would relay the message to the others.

The demonstrators have not put any obstructions on the tracks but are set up nearby — too close for trains to pass safely. The tracks run just outside the reserve boundary of Tyendinaga within its claimed territory.

Via said it will refund the cancelled trips, but that could take up to 10 days due to the volume of transactions.

Murat urged passengers to contact CN about "any progress" on the removal of the blockade. She said passengers will be given details about their trips by email and are urged to go to Via's website for updated schedules.

Via added it remains hopeful that the situation will be resolved.

Via service continues from Toronto to southwestern Ontario, between Montreal and Ottawa and Montreal and Quebec City.

An enforcement officer reads a court injunction to demonstrators on Tuesday. (Lars Hagberg/Canadian Press)

Rail service was also disrupted in B.C. between Prince Rupert and Prince George by a blockade near New Hazelton.

In eastern Ontario, CN said the shut-down is affecting shipments ranging from propane to feedstock, and has disrupted the only rail link between Eastern and Western Canada and the U.S. Midwest.

The OPP is calling on the demonstrators to abide a court injunction and not jeopardize public safety.

"Our primary goal is always to preserve the peace and maintain a safe environment for everyone. We remain open to dialogue that could lead to a peaceful and safe resolution," Bill Dickson, spokesperson for the OPP's East Region, said in an email on Tuesday.

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