Thousands of people every day are on the move across Mexico towards the border with the US. But for migrants, this is one of the most perilous journeys in the world: land routes are dominated by powerful drug cartels and organised crime groups.In this episode of Border Stories, Linda Pressly hears terrifying stories of kidnap and extortion from those who have risked everything to enter the United States. The US/Mexico border has become the most important battleground for Americans in this year’s presidential election, but it seems no one can stop the men with guns who operate with impunity south of the border in Mexico.