This is the first in a series of Spectrum News reports from the U.S.-Mexican border.

GRANJENO, Texas — A homemade wooden ladder used to scale the concrete edge of a levee lies abandoned on the side of the road in this tiny border settlement. It was left here by a recent surge of migrants, which has overwhelmed the U.S. immigration system and created a border crisis roiling President Joe Biden’s first months in office.

In February, the U.S. Customs and Border Patrol encountered 100,441 total cases along its southwest border with Mexico, a 30% increase from the month before. A year ago, in February 2020, the southwest border had 36,687 encounters with migrants. 

While migrant surges happened during previous administrations — the last big surge occurred in 2019 — this year’s wave includes a significant increase in unaccompanied minors.

So far this year, 7.5% of some 100,000 migrants coming across the southwest border have been unaccompanied minors, according to U.S. Customs and Border Protection statistics.

The large number has created a bottleneck in an immigration system struggling to process them quickly enough. As a result, thousands of minors are currently being held in border control detention centers and makeshift federal tent shelters not constructed to accommodate children and teenagers.

The situation has created a political challenge for Biden, who promised his administration would be more humane as it sought to overturn many of former President Donald Trump’s immigration policies.

Republicans have seized on the opportunity to label it a failure of the new White House.

“This is a human heartbreak… There’s no other way to claim it than a Biden border crisis,” said House Minority Leader Kevin McCarthy, a Republican from California, at a press event in El Paso on Monday. McCarthy led a delegation of about a dozen other lawmakers to the western Texas city to tour a migrant processing center and to meet with border patrol.

“It’s becoming a national security concern,” he said. A statement from McCarthy’s office cited the mayor of Uvalde, a city southwest of San Antonio, as saying that he feared some of the migrants “were armed” and that residents were worried about letting their children play outside.

Ahead of a trip to Laredo last week, Republican Texas Sen. John Cornyn said that the immigration issue was no longer a political one.

Biden, on Saturday, directed the Federal Emergency Management Agency to assist Texas and other states struggling to deal with the rapid influx of migrants. The directive instructs FEMA to work with local authorities and federal agencies to receive, shelter, and transfer unaccompanied children, of which an estimated 4,000 are believed to be currently in Texas in border control facilities.

So far this year, about 29,700 unaccompanied minors have come into the U.S. In 2020, the U.S. Customs and Border Protection registered a total of 33,239 unaccompanied minors, putting this year’s cumulative number close to surpassing last year’s total number in just a few months.

A large number of unaccompanied minors in this wave has raised concerns as memories of minors being held in 2018 in temporary detention centers under former President Donald Trump were heavily criticized around the world.

Trump, last year, announced that his administration would close the border to asylum seekers, including unaccompanied minors, because of an emergency health order related to the Coronavirus pandemic.

After taking office in January, Biden said he would resume letting asylum-seeking minors in for processing, a move Republicans said was a sign that the new president was trying to roll back Trump’s attempts to implement strict immigration reform.

Democrats are also concerned about the growing problem, especially in the Rio Grande Valley.

The crisis comes as the Rio Grande Valley struggles to deal with COVID-19 while Texas slowly rolls out its vaccination administration. Texas has one of the lowest vaccination rates across the country, with less than 10% of its population fully vaccinated.  

Rep. Vicente Gonzalez, D-McAllen, who represents the region, wrote a letter to Biden asking for “the adoption of common-sense solutions to relieve border agents and communities bearing the brunt of the recent influx of migrants.”

When asked about the conditions of the minors being held in detention centers at the southern border, White House Press Secretary Jen Psaki acknowledged that the customs and border centers were not meant for long-term housing of children.

Psaki said the situation was heartbreaking and very emotional as well as very challenging, which is why Biden has taken action to expedite getting them out of the border patrol facilities as soon as possible.

“We are trying to work through what was a dismantled and unprepared system because of the role of the last administration,” Psaki told reporters Monday at a news conference at the White House. “It’s going to take some time, but we are very clear-eyed about what the problems are and putting forward some solutions.”

“It’s not acceptable, but I think the challenge here is there are not that many options,” Psaki said. The options are limited to sending the children back home, sending them to unvetted sponsors, or expedite moving them into shelters, where they could receive more suitable accommodations, including medical care, as well as educational and legal resources, she said.

As part of that assistance, FEMA will bus as many as 3,000 migrants, mostly teenagers, to be housed in Dallas’ convention center. The federal agency said the Kay Bailey Hutchison Convention Center would be used to house migrant boys aged 15 to 17 for as much as 90 days.

Meanwhile, the U.S. Health and Human Services department is scrambling to open more facilities across the country to temporarily house the large number of unaccompanied minors coming across the border. HHS is responsible for housing unaccompanied minors once they are processed through border control and until they can be placed with a vetted sponsor through the HHS’ Office of Refugee Resettlement.

“This is an across-the-administration effort and we are committed from the top to making changes as quickly as possible,” Psaki said.

Adult migrants are processed and then sent back across the border if they cannot prove that they have a “credible fear” of returning to their home countries. Processed asylum seekers receive a citation from border control, and are then allowed to go on to a destination within the U.S. and immediately turn themselves in to immigration authorities to begin the legal process.