Venezuelan migrants attempting to enter the United States through Mexico protested a new US program that allows 24,000 people from the country suffering under US sanctions to enter legally while deporting all others who cross the southern border illegally.

On Friday, 70 Venezuelans marched in chains across the Gateway International Bridge in Matamoros, Mexico, across the border from Brownsville, Texas, asking to be allowed on US soil.

The demonstrators, who were among the first deportees under the new immigration rules, dressed in the uniforms of the detention facilities where they were held before being transferred back to Mexico.

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Washington and Mexico City announced on Wednesday an agreement that would allow 24,000 Venezuelans to enter the United States if they could prove sponsorship and only if they flew into the country. As part of the agreement, US President Joe Biden's administration stated that any Venezuelans caught illegally crossing the border would be immediately returned to Mexico.

The program launched a month before the elections is Biden's attempt to find a middle ground between Democratic and Republican demands. The agreement stems from former President Donald Trump's controversial push to keep Central Americans fleeing poverty and violence inside Mexico while their claims are processed.

Some of the protesters, who were on the verge of tears, claimed they had been duped by US authorities because they had already been in the country for ten days. "They deceived us, saying that we were going to [the immigration office] when it was a lie (...) they didn't tell us anything either, just walk, walk," Jonathan Castellanos, one of the Venezuelans, told AFP.

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Confused, Castellanos stated that he only realized he was back in Mexico after a woman in line to cross into the United States pointed it out to him. "What do you mean, Mexico? And that's when it dawned on us," he recalls.

The group remained on the bridge for about five hours, before it was shut down while US authorities set up barbed wire barricades and deployed numerous border police.

After talks with the local border patrol chief, the Venezuelans left the bridge.