Hundreds of Central Americans from a new migrant caravan tried to storm into Mexico Monday by fording the river that divides the country from Guatemala, but National Guardsmen fired tear gas trying to force them back. The Central Americans, from the so-called “2020 Caravan” of around 3,500 undocumented migrants, gathered on the Guatemalan side of the Suchiate River at dawn, demanding migration authorities let them continue their journey to the United States. Scores of migrants, many with cloths tied around their faces to protect them from the gas, pelted the military police guarding the river with large stones, as the latter sheltered behind riot shields.