TAPACHULA, Mexico (AP) — Hundreds of migrants from Africa, the Caribbean and Central America have found themselves corralled in a migrant detention facility in southern Mexico after a futile attempt to head north as part of a caravan aiming to reach the United States.

The group set out before sunrise Saturday from the town of Tapachula, where many had been marooned for months unsuccessfully trying to get transit visas. They carried heavy backpacks, babies and parcels on their heads.

Just before dusk, after having trudged more than 20 miles north, they were surrounded by hundreds of National Guard agents and police who persuaded the exhausted migrants to board vans back to Tapachula. Children cried, and women complained angrily about waiting months for papers. It was unclear if any would be deported.