TECÚN UMÁN, Guatemala—A caravan of Central American migrants seeking to reach the U.S. is set to swell in coming days as thousands gather at Mexico’s southern border waiting for humanitarian visas that have become much easier to get under Mexico’s new government.

Around 5,600 Central Americans are awaiting visas at Tecún Umán, on Guatemala’s border with Mexico, Mexican officials said Tuesday. The visas would allow them to continue their journey north without the risk of deportation from Mexico.

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