Maritza Hernandez arrived at this remote Guatemalan village exhausted, with two young kids in tow and more than a thousand miles left to travel. She was motivated by a simple — if not entirely accurate — story.

"I heard news they are letting children in," said Hernandez, explaining she planned to cross the U.S. border in Texas and seek asylum.

The number of immigrant families apprehended by U.S. agents along the southern border nearly tripled in February from a month earlier to about 19,000 people. Hunger and poverty are spurring their flight. So is disinformation that has rocketed across social media and by word of mouth that the U.S. border is now wide open.