As protesters swarmed Canada’s capital, Ottawa, for the third weekend in a row to vent their anger about pandemic restrictions, police in Windsor, Ontario, struggled to tame a blockade at the Ambassador Bridge, a crossing at the U.S. border that is vital to the supply chains of the global automotive industry.

By Saturday night, the bridge was still closed. Police had driven some protesters away in the morning, forming a line to push them back, but others stayed, and the crowd swelled as the day went on, despite frigid temperatures.

"We don’t have a time frame actually, that’s something that we’re not imposing,” Deputy Chief Jason Bellaire of the Windsor police said Saturday afternoon. "They are professionals, they know what they’re doing, and they are pacing themselves.”