World Bulletin / News Desk

Thousands of Cubans stranded in Panama, many increasingly desperate and penniless, demanded Thursday that borders closed to them in Central America be reopened to allow them to reach the United States.

A growing mass of around 3,000 Cubans on the Panama-Costa Rica border risk triggering another regional migration crisis, weeks after 8,000 compatriots were cleared out of Costa Rica on special flights to El Salvador or Mexico in what officials insisted was a one-off operation.

Nicaragua and Costa Rica have since late last year closed their frontiers to any more Cubans.

But citizens of the Communist island keep coming, lured by America's Cold War-era policy of guaranteeing them easy entry and a fast-track to residency.

On Wednesday, about 1,200 migrants -- most of them Cubans, but also some from Africa and Asia -- stormed the border, overwhelming officials and entering into Costa Rica.

Within hours though, all but 120 of them were convinced to go back into Panama to await a new solution for them.

Panama and Costa Rica are both exasperated with the US policy which they say acts as a magnet. 

Costa Rica accused Washington of maintaining a "perverse" stance in welcoming only Cubans. President Luis Guillermo Solis wrote a letter to his US counterpart Barack Obama complaining about the situation.

Panama's security minister, Rodolfo Aguilera, said: "This isn't a problem we've caused ourselves... We're only a transit country."

In Paso Canoas, a town on the Panama-Costa Rica border, the Cubans are sleeping in improvised shelters in shops and old buildings with no electricity or water. 

Some of them walked in suffocating tropical heat to the border to press their demand to be allowed through.

"We want to keep going," they yelled as around 20 Costa Rican police prevented them from passing through. Security has been tightened along the border since Wednesday's violent scenes.

One of the Cubans, a 60-year-old doctor named Ileana Bordonado, told AFP that "we cannot continue in these inhuman conditions."

She said she had been in Panama for two months following a harrowing journey through Ecuador, and then through Colombia, where police systematically extorted their money until none was left.

"We left all we had on the trip. We don't have anything. It is urgent for us to reach our destination," she said, adding she was aiming to reunite with her son in Tampa, Florida.

Another Cuban, Alen de Jesus Chavez, a 35-year-old physical education teacher, apologized to Costa Rica for the border incident on Wednesday.

"We are not trying to disturb the peace, we are just standing up for our rights and we will stand united until the governments find a solution for us to be on our way," he said.

He said he had left his wife with their two children in Cuba while he made the gruelling overland trip to the US, where he intended to apply for family reunification permission.

 Migrants from DR Congo  

Some of the Cubans noted that Costa Rica had organized frequent flights between January and March this year to transport around 8,000 of their compatriots who had become blocked by Nicaragua's border closure to them.

While Costa Rica has stressed that it would not make such arrangements again, the migrants suggested alternatives.

"The governments should look at an air bridge to Puerto Rico," said one, Leonel Sanchez Lazo.

"Each Central American country should give us a 24-hour transit authorization to pass through. None of us want to stay in any of these countries," said another, who declined to be identified.

The Cubans' plight is being deepened by a small but growing presence of Africans also wanting to cross through. 

Most are from the Democratic Republic of Congo, and they often started their cross-continental trek in Brazil, with the US also their desired destination.

Around 40 of them were arrested by Costa Rican police in the border scuffles on Wednesday, including some children and women.

"We are hungry and we have no money," said one of the Congolese, who identified himself as Chaiden, 34.

"We need help to get to the United States," he said, speaking in a mix of Spanish and Portuguese.