Updated

Mexican immigration authorities say they have returned 104 migrants by plane to Honduras.

The flight back to Honduras on Saturday came amid pressure on Mexico from the government of President Donald Trump to clamp down on migration to the U.S.

Mexican officials are now sorting through a backlog of petitions for transit or humanitarian visas in southern Mexico. Frustrated by long waits for visas and overcrowding at shelters, many migrants are opting to continue north without Mexico's blessing.

The National Migration Institute said that more than 600 Cuban nationals broke out of the Siglo XXI migration station in Tapachula, Chiapas on Thursday. The civil servants manning the station are unarmed, the institute said.