Faced with increasing numbers of Central American migrant children flowing into the country, the U.S. Department of Health and Human Services (HHS) loosened child protection policies through the past few years, allowing dozens of them to be placed in situations where they were neglected, sexually assaulted and starved during the resettlement process, according to a special investigation by the Associated Press published this week.

The report reveals that in 2014, the HSS, which is responsible for protecting unaccompanied minors who are caught attempting to cross the U.S.-Mexico border illegally, stopped fingerprinting people seeking to claim children, stopped verifying their identities, and failed to do criminal background checks in order to move children more rapidly through temporary shelters and into sponsors' homes.

"We are not taking shortcuts," HHS spokesman Mark Weber told the AP. "The program does an amazing job overall."

The AP identifies at least two-dozen children who were victims of sexual abuse and neglect after being released to their sponsors. A related six-month bipartisan Senate probe was prompted by a situation in Ohio, where at least six Guatemalan children were forced to work 12-hour days on egg farms in Marion County, according to Reuters. Six people have now been charged in the case.

According to Republican Senator Rob Portman, who chairs the subcommittee, "more than 30 cases involving serious indications of trafficking and abuse" were reviewed, CTV News reported. "HHS told us that it is literally unable to figure out how many children it has placed with convicted felons, what crimes those individuals committed, or how that class of children are doing today."

The AP's report also says that it is difficult to determine the total number of children exposed to dangerous conditions, because many of the migrants designated for follow-up could not be located when caseworkers tried to contact them.

"You go to pick up a case and sometimes the kids have already moved. Maybe the whole family has moved," said Lavinia Limon, chief executive of the U.S. Committee for Refugees and Immigrants. "It's fairly common that the kid won't be there."

There has been a surge in the number of children crossing the U.S.-Mexico border through the past four years, The Washington Post noted, with most of them fleeing drug cartel-related gang violence and domestic abuse in El Salvador, Guatemala and Honduras. Since 2011, more than 125,000 unaccompanied minors from Central America have been taken in at the border, often placed in shelters funded by the federal Office of Refugee Resettlement.

The HHS told the AP that they are planning to open new shelters with up to 2,200 new beds, and a national call center where children and sponsors can report issues has also been created. The organization notified Congress last month that an additional $400 million was needed in order to provide shelter and referral services to the child migrants, but the request has been denied.