SAN DIEGO — In an overcrowded shelter at a sports complex south of the Mexican border, nearly 6,000 migrants from Central America have been waiting in increasingly squalid conditions — and with an increasing sense of desperation — to cross into the United States.
On the other side of the border, though, many of those who have managed to successfully make it across have found that the weeks they spent in Mexico trying to enter the United States have led to even more challenges ahead.
They are waiting, too.
Yarely Elizabeth Palomo, who said she set out from Honduras to the United States six months ago with her young daughter, had to wait behind hundreds of other people for processing when she arrived at the border in Tijuana, and waited two weeks for her number to be called by American immigration authorities.
On Tuesday, two days after a tense standoff in which American authorities fired tear gas at hundreds of migrants who tried to storm the border fence, Ms. Palomo sat in a makeshift shelter in San Diego set up for migrants who have been slowly trickling through the border. She said she was uncertain where she was headed or whether she would be allowed to stay after telling the American authorities about the gang violence that she said drove her from her home.
“I’m here for now. I’m not sure what comes next,” she said.
Most of those at the shelter were not given the traditional screening interviews at the border and said they were not even sure when they would be given the opportunity to apply for asylum in the United States.
“I tried to ask for asylum at the border. They didn’t let me,” said Víctor Manuel Galdamez, a migrant from El Salvador who was waiting at the shelter. “I am still waiting to ask. I have no idea when they will let me.”
The long wait times are partly the product of a Trump administration initiative known as “metering,” which limits the number of people who can be processed through ports of entry each day. Immigration authorities at the San Ysidro border crossing, near San Diego, said they were able to process about 100 migrants each day, though rates have dipped as low as 40 a day. At this rate, it could be five weeks before the first arrivals from a caravan of migrants from Central America could have their interviews for admission to the United States.
For many of those gathered in Tijuana, the wait has become intolerable. On Sunday, several hundred migrants made a run for the border, attempting to scale the fence before American immigration authorities repelled them with volleys of tear gas. Nearly 100 people were arrested by the Mexican authorities and face possible deportation for their participation in the events.
“We know the United States has the resources and capacity to process these asylum seekers much faster,” said Kate Clark, director of immigration at Jewish Family Service of San Diego, which runs an emergency shelter for migrants. “The U.S. government is choosing not to process them.”
Some of those waiting in Mexico have begun to despair.
“The caravan has ended here,” José Mejia, 37, said as he waited — in another line — to register with the United Nations to return voluntarily to Honduras. This was his sixth attempt to enter the United States, he said, and he had seen enough.
“People have a false vision, of something that will never happen,” he said. “The United States is not going to let any of these people in.”
Most of those who had been released to shelters in San Diego this week were migrants who arrived with children. Most of the migrants who crossed alone were being held in detention, and their progress through the system was less clear, said a number of immigration lawyers who had gathered in San Diego to help the new arrivals navigate the asylum process.
Those who hope to remain in the United States must convince American immigration officials that they are worthy of protection, and avoid those factors that can be used to knock them out of qualification, which have grown more plentiful under President Trump.
By the time their individual Judgment Day has come, which can take years, some of the migrants will have paid lawyers to shepherd them through the process. Others will try with no preparation at all, or by drawing on small bits of advice picked up along the journey from smugglers and other migrants.
Even those who prepare for the evaluations say that the process can be grueling, and the results counterintuitive. Ultimately, the majority will be unsuccessful and sent home. Historically, only 20 percent of cases are approved.
“If you don’t know how to present your case, you’re going to lose,” said Eileen Blessinger, an immigration defense lawyer who averages about half-a-dozen asylum cases a week in immigration court in Arlington, Va.
For many, the process will begin with an interview with an American asylum officer to determine whether they have a “credible fear” of returning to their home country. Those who pass the interview will be allowed to proceed with their case. The less fortunate will be swiftly deported.
In court, the migrants can present documentary evidence of their oppression and call on witnesses to support their stories. But they will also be cross-examined by government lawyers, who will look for discrepancies and try to poke holes in their stories.
Since taking office, Mr. Trump has added demands to the process for seeking asylum at each stage, beginning with the “credible fear” interview. Earlier this month, he announced that people would only be able to request asylum in certain places, though that policy has been temporarily blocked by a federal judge. A new proposal under consideration would require asylum seekers to wait in Mexico while their cases are adjudicated.
In Mexico, though the mood was less tense than it had been over the weekend, the conditions had become grim.
Nearly every square foot of the increasingly overcrowded sports complex in which the migrants are housed — originally intended for only about 300 people — is covered in a checkerboard of shelters, ranging from high-tech donated camping tents to makeshift bunkers fashioned out of blankets and plastic sheeting.
Everyone is living cheek by jowl. They bathe under trickles of water that fall from temporary showers near rows of portable toilets that line the outfield fence of one of the baseball diamonds. They survive on donated food distributed from trucks out front.
“It’s very difficult because of the number of people, there isn’t food, the number of toilets are insufficient,” said David Vélez, a Honduran migrant, as he whiled away the morning in a small tent where he had been sleeping with two friends. “There isn’t sufficient space but we try to adjust to the facilities we have.”
Among those thinking of giving up and returning home was Enoc Melgar, 18, from Santa Barbara, Honduras. He had planned to seek asylum in the United States, but when he learned how long he would have to wait, he decided to give up and perhaps try again in the future — though not until the commotion surrounding the caravan had dissipated.
“Ever since we left our country, we thought that everything would turn out well,” he said. “But here we see that we’re not going to accomplish anything, so it’s better to go back to our country.”
Adrián Muñoz Mejia was also having misgivings after Sunday’s confrontation.
“We’ve had a great opportunity, but we have to think carefully about what we’ll do next,” he said. “Because if they grab us on the other side, that’s the end to our aspirations.”