Montreal | Reuters — Canadian National Railway has started calling back many of the 450 workers it laid off earlier this month in Eastern Canada, when blockades crippled operations on strategic rail lines, according to a company email sent to customers Friday.

Earlier this week, police made 10 arrests and cleared a blockade in eastern Ontario that had been stopping freight and passenger traffic for almost three weeks on one of Canada’s busiest lines.

The blockades were held in solidarity with the Wet’suwet’en people in British Columbia, who are seeking to stop TC Energy from building a gas pipeline over their land.

“In the absence of illegal blockades on our network over the last 24 hours, and while we are keeping a close watch for any further disruptions, we have started calling back many of the temporarily laid off employees based in Eastern Canada,” CN CEO Jean-Jacques Ruest said in the email seen by Reuters.

The email did not specify how many of the 450 workers were being called back.

After 21 days of disruptions, “there is a significant backlog of trains parked on our tracks and in our yards that will be processed,” the email said.

“The complete network recovery process will take several weeks.”

Montreal-based CN said the company was on its way to recovering in Western Canada, and said products such as export grain, imported containerized goods, coal, potash and other commodities are moving to market.

Canada relies on CN and rival Canadian Pacific Railway to move crops, oil, potash, coal and manufactured goods to ports and the United States. About half of Canada’s exports move by rail, according to industry data.

— Reporting for Reuters by Allison Lampert in Montreal.

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