Border crossings to Mexico closed by protests Largest display of discontent against the army's crackdown on drug cartels Protesters block a main avenue during a demonstration against the Mexican army in Monterrey, northern Mexico, on Tuesday. The army has blamed protests on drug cartels targeted by the government. Monterrey is not on the border but is southwest of Nuevo Laredo. CIUDAD JUAREZ, Mexico - Hundreds of people blocked bridges to the United States in three border cities Tuesday, demanding the army leave in another challenge for the Mexican government as it struggles to quell escalating drug violence. The protests in...