“Panama cannot end up becoming a black hole for deported migrants,” said Juan Pappier, deputy director of Human Rights Watch in the Americas. “Migrants have the right to communicate with their families, to seek lawyers and Panama must guarantee transparency about the situation in which they find themselves.”

The migrants were flown from San Diego to San Jose, from where they were sent by bus to a migrant shelter near the border with Panama.

Costa Rica is the second Central American nation to accept migrants from distant countries as the Trump administration ramps up deportation flights.

Officials in Costa Rica and Panama are confiscating migrants' passports and cellphones, denying them access to legal services and moving them between remote outposts as they wrestle with the logistics of a suddenly reversed migration flow.

Migrants deported from the U.S. could be held in Costa Rica for up to six weeks before being sent to their home countries, Costa Rican President Rodrigo Chaves said on Wednesday.