WASHINGTON >> The Trump administration is unable to account for the whereabouts of nearly 1,500 migrant children who illegally entered the United States alone this year and were placed with sponsors after leaving federal shelters, according to congressional findings released today.

The revelation echoes an admission in April by the Department of Health and Human Services that the government had similarly lost track of an additional 1,475 migrant children it had moved out of shelters last year.

In findings that lawmakers described as troubling, Senate investigators said the department could not determine with certainty the whereabouts of 1,488 out of 11,254 children the agency had placed with sponsors in 2018, based on follow-up calls from April 1 to June 30.

The inability to track the whereabouts of migrant children after they have been released to sponsors has raised concerns that they could end up with human traffickers or be used as laborers by people posing as relatives.

Since 2016, officials at the Department of Health and Human Services have called sponsors to check on children 30 days after they were placed there. But the department has also said it was not legally responsible for children after they were released from the custody of its office of refugee resettlement.

Caitlin Oakley, a spokeswoman for the Department of Health and Human Services, offered a response to the findings tonight. “As communicated to members of Congress multiple times,” she said, “these children are not ‘lost.’ Their sponsors — who are usually parents or family members and in all cases have been vetted for criminality and ability to provide for them — simply did not respond or could not be reached when this voluntary call was made.”

The findings were accompanied by legislation introduced today by Republican and Democrat senators to clarify the department’s responsibility for ensuring the safety of migrant children, even when they were no longer in its custody.

The legislation would require officials at the Department of Health and Human Services to run background checks before placing children with sponsors. It also would compel the department to make sure that sponsors provide proper care for the children in their custody, including making sure they appear at their immigration court hearings.

Additionally, the legislation would require department officials to notify state governments before migrant children are placed with sponsors in those states. And it would increase the number of immigration court judges to help the Justice Department process cases more efficiently.

Sen. Rob Portman, R-Ohio, chairman of a Senate Homeland Security subcommittee on investigations, said the bill “will ensure that we keep track of unaccompanied minors in our country, which will both help protect them from trafficking and abuse as well as help ensure they appear for their immigration court proceedings.”

Sen. Richard Blumenthal, D-Conn., who also sponsored the legislation, said, “Children who risk their lives to make a dangerous journey in pursuit of asylum shouldn’t then have to worry about falling victim to human trafficking or being handed over to abusive or neglectful adults in the United States.”

In a report two years ago, the Senate subcommittee detailed how department officials mistakenly placed eight children with human traffickers who forced them to work on an egg farm in Marion, Ohio.

The report found that department officials had failed to establish procedures — including sufficient background checks and following up with sponsors — to protect the children who were traveling alone. As a result, the children were turned over to the traffickers who contracted them out to the egg farm.

Since October 2014, the Department of Health and Human Services has placed more than 135,000 unaccompanied immigrant children with adult sponsors in the United States as they wait for their cases to be heard by an immigration judge.

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