On Wednesday, members of The People's Forum left Cuba for the U.S. after taking part in the International Workers' Day in Havana, where they met with President Miguel Diaz-Canel.

Upon entering U.S. territory, however, the Customs and Border Protection Office (CBP) unjustifiably detained The People's Forum members for several hours.

"Multiple members of our youth delegation to Cuba were detained and held for hours by the CBP after returning. Despite having travelled legally, we’ve been harassed and held in Secondary Questioning on arrival to international airports in Miami and Newark," The People's Forum tweeted.

"Our phones were wrongfully searched and seized by CBP. This outrageous behavior seeks to intimidate us and criminalize our right to travel and exchange," it added

"We demand the release of our remaining comrades! We will not be moved! Our commitment to end the U.S. blockade of Cuba will only grow," The People's Forum stressed.

"Cheer up, guys, we are with you," President Diaz-Canel tweeted. "Thank you for your courage, for supporting Cuba and for facing in the monster's very bowels the hatred of those who cannot bear that the Cuban Revolution has the support of the most progressive youth. We send you a big hug."

The People's Forum defines itself as an “incubator for working class and marginalized communities to build unity across historic lines of division at home and abroad. We are an accessible educational and cultural space that nurtures the next generation of visionaries and organizers who believe that through collective action a new world is possible."