(CNN) -- Maximo, an asylum seeker, fled his native Honduras with his son to seek a new life in the United States.
But while waiting for their cases to be heard he says they have practically become prisoners in a shelter for migrants in the Mexican border town of Nuevo Laredo, where cartels prey on migrants who venture out into the streets. He and his son were nearly kidnapped, he says.
"We are alone and only God's hand has kept us safe from the constant danger that surges in this country," he wrote in a letter. "We don't intend to cause any harm to the United States. We would just like a safe place [to wait] for a response from the government."
Maximo is among tens of thousands of asylum seekers who under Trump administration policy must wait in Mexico for their US immigration proceedings.
He and nearly two dozen other migrants at the border responded to a request from Denise LaRock, an American nun who advocates for immigrants, to write letters explaining their hazardous situation. LaRock told the migrants she would share the letters with journalists to bring attention to the dangers they face.
CNN is only using the migrants' first names due to safety concerns and has translated the letters to English.
LaRock has been serving some 200 asylum seekers, mostly from Central America, who live in shelters provided by Lorenzo Ortiz, a pastor from a ministry called El Buen Samaritano Migrante. Among the asylum seekers are a former police officer, a mechanical engineer, a mechanic and a university student.
The shelters, including four churches and one home, are crowded and have little to no furniture. The migrants sleep on cots or on the floor. And the surrounding neighborhoods are so dangerous, they write, that walking outside the shelter could result in kidnapping or death.
"Kidnapping is the daily bread [here]," wrote Maria, another migrant.
"Mexico is the same or worse than Honduras," wrote a third, Elsa. "We are in prison here because of the danger, because the cartels are in every corner."
Thousands of migrants are waiting in limbo
Roughly 60,000 migrants have been returned to Mexico since the start last spring of the administration's "Remain in Mexico" policy, which requires asylum seekers to wait in Mexico for their cases to be resolved. The Trump administration has credited the program with helping decrease the number of migrants arriving at the US-Mexico border and easing the ongoing border crisis.
But Ortiz says the migrants at the border face new dangers. He says the cartels case the bus stations and the streets near the immigration office looking for Central Americans. The asylum seekers, he says, are easy targets because they are usually released by US authorities wearing shoes without laces and carrying a manila folder with documents and a plastic bag with their belongings.
One migrant, Tere, wrote that she and her 7-year-old son were kidnapped once they reached the US border and were held for nine days without food. They were only released after her family paid a ransom, she wrote.
"I thank God for freeing me from that terrible experience," wrote Tere, who says her asylum court date in the US is next February.
In their letters many of the migrants thanked Ortiz, and God, for their survival.
Ortiz told CNN some migrants have been kidnapped more than once and that others have been sexually assaulted or have lost fingers to the cartels. At least four families who were kidnapped have not returned, Ortiz said.
"The danger is real," he told CNN by phone.
A cartel raided one of his shelters at gunpoint about two months ago, he said. But he said the cartel didn't hurt anyone after they learned the shelter was run by a pastor.
Keeping the migrants fed, and safe
LaRock is a US citizen and says she has been crossing the border from Laredo, Texas, in Ortiz's van every Wednesday for the past two months to bring supplies to the shelters.
She packs the van with cooking oil, beans, diapers, blankets, clothes, puzzles and anything else her Interfaith Welcome Coalition can gather to help address the migrants' basic needs.
She also started a GoFundMe page to help Ortiz pay rent, electricity, water and food for the shelters.
LaRock says she hopes the migrants' desperate letters will help other Americans understand how US policies are exposing asylum seekers to some of the same dangers they fled in their native countries.
"My hope is that people... can have compassion," LaRock told CNN by phone.
Meanwhile, the migrants in Nuevo Laredo hope their future will somehow be brighter.
"I regretted leaving my country," wrote Lilian, a Honduran waiting at a border shelter with her daughter, in her letter. But the poverty in Honduras was too severe and her daughter had no future there, she said.
"The goal of every mother is to look for something better for their children."