On the Canadian border, agents look for footprints in snow or mud, a hole in a fence or a rock painted orange as a meeting point anything that could hint at illegal crossings. Down south, agents pull giant tires behind trucks to smooth dirt roads so footprints are more easily noticed.
"It's almost a game of cat and mouse we change one thing, they change another," one agent said.
On the Canadian border, agents look for footprints in snow or mud, a hole in a fence or a rock painted orange as a meeting point anything that could hint at illegal crossings. Down south, agents pull giant tires behind trucks to smooth dirt roads so footprints are more easily noticed.
"It's almost a game of cat and mouse we change one thing, they change another," one agent said.
Illegal immigration is a constant issue in the United States, focused on the southern border. In the north, far fewer agents patrol a vast and often treacherous landscape.