FILE PHOTO: Migrant boys spend time in a recreation area outside Casa Padre, an immigrant shelter for unaccompanied minors, in Brownsville, Texas, U.S., June 23, 2018. REUTERS/Loren Elliott/File Photo

By Ted Hesson and Emily Green

WASHINGTON (Reuters) - A federal judge on Thursday ordered the Trump administration to refrain from deporting Guatemalan unaccompanied migrant children with active immigration cases while a legal challenge plays out.

Judge Timothy Kelly, a Trump appointee based in Washington, D.C., kept in place an earlier judicial block on the policy, sharply criticizing the administration's unproven assertion that the children's parents wanted them deported.

U.S. President Donald Trump's administration attempted to deport 76 Guatemalan minors being held in U.S. custody in a surprise move in the early morning on August 31, sparking a lawsuit and emergency hearing that temporarily halted the move.

Justice Department lawyer Drew Ensign initially said that the children's parents requested they be returned home, but the department later rescinded that claim.

The reversal came after Reuters published an internal report by a Guatemalan attorney general showing that most parents of the roughly 600 Guatemalan children in U.S. custody could not be contacted. Of those contacted, many did not want their children returned to Guatemala, the report said.

In a 43-page opinion, Kelly said the Trump administration's explanation "crumbled like a house of cards" in light of the Guatemalan government report.

"There is no evidence before the Court that the parents of these children sought their return," Kelly wrote.

The U.S. Department of Homeland Security and Department of Justice did not immediately respond to requests for comment.

Kelly blocked the rapid deportation of Guatemalan unaccompanied children who have not received a final removal order or permission from the U.S. attorney general to depart while their cases remain active.

In the ruling, the judge said the children were unexpectedly taken from their shelter beds in the middle of the night, driven to the airport and, in some cases, put on planes, leaving them worried and confused.

At one shelter in McAllen, Texas, a young girl was so scared that she vomited, Kelly wrote, citing evidence submitted in the case.

Lawyers for the children filed a lawsuit seeking to block the removals, prompting an emergency hearing over the Labor Day weekend.

Migrant children who arrive at U.S. borders without a parent or guardian are classified as unaccompanied and sent to federal government-run shelters until they can be placed with a family member or foster home, a process outlined in federal law.

A Guatemalan mother whose 16-year-old son could be subject to the Trump administration deportation effort told Reuters that her son would like to remain in California even though she misses him.

“This is what he wanted,” she said during an interview earlier this month on the outskirts of Guatemala City.

The mother, who spoke to Reuters on condition of anonymity, works 15 hours a day at a restaurant and makes just enough money to cover rent and food, she said.

(Reporting by Ted Hesson in Washington and Emily Green in Guatemala City; additional reporting by Sofia Menchu in Guatemala City; Editing by Rosalba O'Brien)