ROMA, (United States): Oscar is 12 years old and has just crossed the Rio Grande river from Mexico to Texas in a small, inflatable boat piloted by human traffickers. He is tearful, hungry and afraid after a dangerous month-long journey from Guatemala.

His first words upon arrival in the United States: “Vengo solo (I come alone).”

“I came here because we didn’t have anything to eat,” the thin boy with big brown eyes tells AFP as nightfall settles on the Rio Grande Valley. A surge in migrants at the United States border with Mexico has emerged as one of the major challenges facing Democratic President Joe Biden just two months after taking office. Unaccompanied children and thousands of families have been allowed in at a time when the Border Patrol’s processing facilities and government detention centers are full to overflowing. For his part, Oscar hopes to be reunited soon with his uncle — a house painter who has lived in Los Angeles for 15 years — after his traumatic trip.

Before leaving, “My mama told me: ‘Don’t cry.’ But I cried,” says Oscar, the only son of a single mother who lost her job as a cleaning woman because of the Covid-19 pandemic. He is unable to hold back his tears.

The worst part of the journey, Oscar says, was the 12 hours spent in a trailer packed with migrants near the border with Mexico.

“It was hot and everyone started to faint,” he says. Oscar did too, until someone gave him water.

But he has a fond memory of a friend met along the way, who he later lost track of.

“He told me not to give up, that we had to make it, with God’s mercy. And he told me I was going to have a better life there.”

In the United States, he says, “I’m going to be able to study. I’m going to learn how to bring my mama.”

More than 70 undocumented immigrants — nearly all from Guatemala or Honduras, but two from Romania — crossed the Rio Grande to Roma on Saturday night in arrivals witnessed by AFP. More than 20 of them were unaccompanied children or adolescents, some as young as seven.

Upon arrival, the migrants walked close to a mile (more than a kilometer) along a sandy path through thorny bushes to surrender to waiting US Border Patrol agents. The path was littered with artifacts of the migrants’ old lives, objects lost or cast aside: the colored plastic bracelets that the traffickers place on their human charges to identify them when crossing the river, the odd shoe, a pair of wet pants, a baby’s rattle, Honduran money.

The authorities will try to reunite the minors with family members. Some families will be freed to await their asylum hearings, others will be deported. Adults who arrive alone are all deported, the government has said. Scenes like this are repeated daily, with arrivals numbering in the hundreds some nights, according to residents here.

Biden is facing political attacks over his policies for the nearly 2,000-mile (3,200-kilometer) border with Mexico, with Republicans accusing him of fueling the surge after predecessor Donald Trump sought to seal off the border.

Even while moving to dismantle many of Trump’s immigration policies, Biden has insisted that the border is not open and that most undocumented migrants are quickly deported.

“We are not going to send children under the age of 18, kids under the age of 18, back on this treacherous journey,” White House spokeswoman Jen Psaki said on “Fox News Sunday.”

“It does not mean that they get to stay in the United States... we want to treat them humanely, make sure they are in a safe place while their cases are adjudicated.”

In February, nearly 100,000 migrants illegally crossed the border, a return to mid-2019 levels after a slowdown caused by the pandemic.

More than 9,400 minors crossed the border alone and surrendered to authorities last month, a 28 percent jump from January. And more than 14,000 have arrived so far in March, according to authorities, who expect the numbers to continue to rise.

More than a dozen migrants interviewed by AFP just minutes after setting foot on US soil said their chief reasons for coming were poverty, violence and joblessness, all aggravated by the pandemic and the devastating impact of recent hurricanes in their countries, mainly Honduras, El Salvador and Guatemala.