TORONTO - Protesters blockaded a third U.S.-Canada border crossing on Thursday, escalating a crisis that's leading automakers to cut production, weighing on the economies of both countries and prompting U.S. officials to call for their Canadian counterparts to intervene.

The Royal Canadian Mounted Police said Thursday that the Emerson crossing between Manitoba and North Dakota was "shut down," after a large convoy of vehicles and farm equipment blocked traffic in both directions. Demonstrators protesting vaccine mandates and coronavirus restrictions have also blockaded border crossings at Coutts in Alberta and the Ambassador Bridge.