The letter also said that DHS told the committee that new restrictions would be placed on staffers’ access to facilities run by U.S. Immigration and Customs Enforcement, which falls under DHS.

“I am writing to express my deep concern that the Department of Homeland Security (DHS) decided to block Committee staff from conducting visits to 11 detention facilities just days after previous staff inspections revealed potentially serious ongoing problems with the treatment of children and adults in DHS custody ― including blocking visits to sites where the Inspector General warned about ‘an immediate risk to the health and safety of DHS agents and officers, and to those detained,’” Cummings wrote in the letter.

Committee Chairman Rep. Elijah Cummings (D-Md.) sent a letter Thursday to Acting DHS Secretary Kevin McAleenan objecting to the agency’s last-minute decision to block committee staff from visiting this week, and requesting DHS allow “meaningful access” to these facilities again.

The Department of Homeland Security is blocking House Oversight Committee staff from visiting migrant detention centers after previous committee inspections revealed serious problems at the border facilities, according to the committee.

BREAKING: After Committee inspections of #DHS immigration facilities found serious problems, #DHS abruptly blocked further staff visits. @RepCummings requests #DHS provide meaningful access to the identified #ICE and #CBP facilities. https://t.co/ScafwduCt0

Cummings said the decision to bar committee staff goes against McAleenan’s congressional testimony last month in which he said he welcomes such visits to detention centers.

DHS did not immediately respond to HuffPost’s request for comment.

Last month, the Inspector General of DHS released a report warning of severe overcrowding at some migrant detention centers, citing dangerous and unsanitary conditions, like a lack of shower access and room to lie down.

Cummings’ letter contained similar concerns, saying migrants told committee staff during earlier trips to Border Patrol facilities that toddlers were being fed age-inappropriate food, young children were being held in cold rooms without proper clothing, and even that a Border Patrol agent told a child to drink spilled soup off the floor.

Migrants at the facilities also told committee staff that agents pressured them into signing documents in English without proper translation or phone access, according to the committee chairman.

During visits to ICE facilities ― many of which are run by for-profit contractors ― migrants told committee staff that they were being given rotten food and inadequate medical care access, the letter stated.

Cummings cited an instance at the Adams County Correctional Center in Mississippi, where an ICE officer threatened to immediately end the congressional tour and cancel future visits after a detained migrant shouted through a glass partition that he wanted to speak with committee staff because he was allegedly being abused and humiliated at the facility.

The letter came after Rep. Jim Jordan (R-Ohio), the committee’s ranking member, said that the panel’s staff were being “rude” to officers at the facilities. U.S. Customs and Border Protection also alleged that committee staff weren’t cooperating with officers, Cummings’ letter stated.

But Cummings said the claims were false, and that committee staff cooperated with DHS “while defending the authority of Congress to conduct an independent investigation of these well-documented abuses.”

“It appears that the Administration expects Congress to be satisfied with receiving agency tours of facilities ― in some cases without the ability to photograph conditions or interview detainees ― and not to question the policies or decisions that agency officials make,” Cummings wrote in his letter.

“That is not the way effective oversight works,” he continued. “Congress has an independent responsibility under the Constitution to determine whether federal programs are operating as they should be ― not merely to accept the Administration’s word for it.”

Read Rep. Cummings’ letter to DHS below: