Canadian officials and experts believe that the jump in illegal crossings has been fueled primarily by immigrants arriving in Canada from India on tourism or other temporary visas.

In a characteristically bombastic threat to slap hefty tariffs on Canadian and Mexican imports to the U.S. once he takes office next year, president-elect Donald Trump said he was motivated by border issues between those countries and his own.

Donald Trump threatened to impose sweeping new tariffs on Mexico, Canada and China as soon as he takes office. Here's what to know.