MATAMOROS, Mexico (Reuters) - For a few precious hours, Luz thought she would soon see her children again.

FILE PHOTO: Migrant girls, asylum seekers sent back to Mexico from the U.S. under the "Remain in Mexico" program officially named Migrant Protection Protocols (MPP), are seen playing at a provisional campsite near the Rio Bravo in Matamoros, Mexico February 27, 2020. REUTERS/Daniel Becerril

The 42-year-old Peruvian is one of about 2,000 migrants, mostly seeking asylum in the United States, who are living in a sea of tents on the banks of the Rio Grande in Mexico, within view of the frontier fence.

On Friday afternoon, a U.S. court blocked the Trump administration’s “Remain in Mexico” policy that has forced them to wait south of the border as their cases proceed.

The policy is central to President Donald Trump’s quest to reduce the number of people granted entry to the United States. If the ruling is upheld, it would be a blow to Trump, a Republican, as he runs for a second term in office, with hardline immigration policy central to his campaign.

As word of the court’s ruling raced through the camp in the Mexican border town of Matamoros, few were more elated than mothers and fathers like Luz who have made the wrenching choice to send their children to cross into the United States alone.

The “Remain in Mexico” program, also known as Migrant Protection Protocols, does not apply to unaccompanied minors, so some parents have sent their children hoping they can stay with relatives in the United States, rather than camping out for months in one of Mexico’s most dangerous cities.

When news of the ruling reached Luz, her eyes filled with tears. She envisioned a reunion with her 11-year-old daughter and nine-year-old son, whose faces she has only seen over video chat since they entered the United States nearly a month ago.

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But hope dimmed quickly. Hours later, the court’s decision was suspended to allow the government to ask the Supreme Court to take up the issue, leaving Luz and others with nothing but a new set of questions.

“All I think of is being with my children,” said Luz, who said she left Peru due to domestic violence. “I need my children and my children need me.”

Desperation has pushed many parents to make the same choice, fearful of the poor sanitation and risk of kidnapping or worse if they stay in Matamoros.

Luz knew her children couldn’t stay. Her daughter, who is disabled, struggled with life in the camp and would scream in frustration.

“I can live here, but my children couldn’t stand it,” said Luz, shielding her face from the sun with a white baseball cap embroidered with the letters “USA.”

In early February, she sent her children across the bridge. Since then they have stayed in a U.S. government facility as Luz works to provide the necessary documentation so they can be released to a cousin.

U.S. Customs and Border Protection did not immediately respond to a request for comment.

At least 50 unaccompanied minors made the same trip into the United States from Matamoros in 2019, local activists say, and the trend has continued this year.

As Edixson Sanchez trekked from Venezuela to the United States, his seven-year-old son was always by his side. But shortly after the pair were returned to Matamoros, Sanchez, 39, saw the men who had kidnapped them earlier on their journey lurking near the camp. He sent his son to the bridge the next day.

On Saturday, Sanchez called his son, now in the United States with his mother, listening helplessly as the boy cried.

Desperate to stop his son’s tears, Sanchez reassured him that he would join him soon, though he still has no idea when that day will come.