Abel Oset was seized with panic. After an 11-country odyssey that began when he and his namesake son fled Cuba, and included a moment on U.S. soil, he was crossing back into America.

But he wasn’t sure he’d be able to stay.

The two were going to plead their case in a court set up inside a tent in Laredo, Texas, beamed via video conference to a judge in another city — the latest attempt to clear a massive backlog of asylum cases.

They were among more than 100 migrants on Tuesday’s docket — though only 38 had arrived. So much depended on this hearing; Oset dreaded the very real possibility that he and his 22-year-old son would be sent back over the international bridge, back to Nuevo Laredo, in Tamaulipas, and its cartels and violence.

Awaiting his hearing in the pre-dawn hours, Oset lay on the floor of a migration building. He spoke of the criminals who stalk the bridge, picking off migrants. He and his son were targeted by kidnappers twice but had no money and were turned loose with warnings not to return.

“Those who arrive are being taken, one by one,” he said.

Some migrants awaiting hearings arrived at the bridge before sunset Monday from Monterrey, hundreds of miles from the border. Others left city hostels early to avoid moving at night.

At least 42,000 migrants have been forced back into Mexico after crossing the border, according to the U.S. government. Many of them say they fled violence or threats in their home countries and hope to get asylum.

The Department of Homeland Security has said it planned to spend $155 million to build and operate the tent courts but expects the costs to be less. But critics have denounced the proceedings because they are closed to the public and difficult for attorneys to access.

President Donald Trump’s top lieutenants on immigration and border enforcement toured the tent complex in Laredo on Tuesday, defending the “remain in Mexico” policy. The complex includes several rooms where court hearings are held, people wait and children can read storybooks in Spanish.

During the tour, there were 15 immigrants in a processing room and two dozen in a room where migrants await a decision on their case. With the temperature outside approaching 100 degrees, air conditioning units blasted cold air through the tents, creating a din that makes it difficult to hear.

Many of the migrants making court appearances complain of the dangers they face as they are forced to wait in crime-ridden Nuevo Laredo. The U.S. government has warned Americans not to travel to the area, citing safety concerns.

Acting Homeland Security Secretary Kevin McAleenan defended the “remain in Mexico” policy, calling it a reasonable alternative to separating and detaining families in the U.S.

“You are seeing a team effort across four agencies and two departments to run an expeditious lawful process so that families are staying together during their process so that they can wait in a non-detained setting for their hearing,” he said.

“We’re getting more integrity into the system to deter those who don’t have valid claims from making the journey,” McAleenan added.

For Trump, curbing immigration remains his signature issue, and his administration also is dealing with a massive increase in migrants, mostly Central American families, that has strained the immigration system. A major aim of these programs is to deter people from coming to the southern border.

Mexico has cracked down on migrants coming to its southern border, and the U.S. is working on diplomatic agreements with other Central American countries.

The U.S. Supreme Court last week made it vastly more difficult for people to win asylum, allowing the new rules into effect during litigation challenging them. The rules bar anyone who passed through another country from claiming asylum, though some other protections may still be available.