HOUSTON – When officers led them out of a detention facility near the U.S.-Mexico border and onto a bus last month, the 12-year-old from Honduras and his 9-year-old sister believed they were going to a shelter so they could be reunited with their mother in the Midwest.

They had been told to sign a paper they thought would tell the shelter they didn't have the coronavirus, the boy said. The form was in English; the only thing he recognized was the letters "COVID."

Instead, the bus drove five hours to an airport where the children were told to board a plane. "They lied to us," he said. "They didn't tell us we were going back to Honduras."

More than 2,000 unaccompanied children have been expelled since March under an emergency declaration enacted by the Trump administration, which has cited the coronavirus in refusing to provide them protections under federal anti-trafficking and asylum laws. Lawyers and advocates have criticized the administration for using the global pandemic as a pretext to deport children to places of danger.

No U.S. agents looked at the video the boy had saved on his cellphone showing a hooded man holding a rifle, saying his name, and threatening to kill him and his sister, weeks after the uncle caring for them was shot dead. And even though they were expelled under a declaration citing the virus, they were never tested for it, the boy said.

Three weeks after their uncle was killed, the children fled Honduras, crossing the U.S.-Mexico border alone. Under the normal process set out by U.S. law, they would have been referred to a government facility and eventually placed with their mother. Instead, they were expelled on July 24 after three days in U.S. detention.

U.S. Customs and Border Protection declined multiple requests for comment on the boy's story, and U.S. Immigration and Customs Enforcement also declined.

Spokesmen for both agencies have refused to answer most questions about how they treat about 70,000 adults and children expelled under the emergency declaration issued in March. They have refused to say how they decide whether to expel children or where to detain them before expulsion.

Six children have died since 2018 after being detained by the Border Patrol, several in conditions that raised questions about how the agency treats children. The agency says it has instituted new medical checks and takes anyone determined to need additional care to a hospital.

Mark Morgan, the acting Customs and Border Protection commissioner, said Thursday that expulsions conducted under a section of U.S. public health law known as Title 42 were necessary to protect his agents. Morgan said 10 CBP employees have died after contracting COVID-19. "There's no doubt that Title 42 has prevented more tragic loss among our own workforce," he said.