Kevin McAleenan, the acting secretary of the Department of Homeland Security (DHS), is testifying before the House Oversight and Reform Committee about the conditions in migrant detention centers at the border and the Trump administration's restrictive immigration policies.

In his opening statement, McAleenan urged Congress to act to stem the influx of migrants at the border, saying that "a durable solution to this crisis lies with Congress." McAleenan also condemned "incendiary and overwrought attacks" on Customs and Border Protection (CBP) officials by some members of Congress who have criticized conditions at detention centers were "unwarranted and damaging."

McAleenan also said during the hearing that the results of an investigation into private Facebook groups with current and former CBP officials mocking migrants and members of Congress will be released "this month or early next month."

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McAleenan's testimony comes the week after the committee held a hearing on the treatment of migrants at the southern border, amid multiple reports of poor conditions in detention centers, featuring testimony from members of Congress who had visited such facilities.

Rep. Alexandria Ocasio-Cortez gave passionate testimony about her visit to a border facility in that hearing, telling the panel Friday morning that "the cruelty (at the border) is manufactured" by hard line immigration policies ordered by the president.

Last week the acting DHS inspector general, Jennifer Costello, told the panel that CBP requires "immediate assistance" to address the "acute and worsening crisis" of overcrowding in CBP facilities. She also said that there was concern in the office of the inspector general (OIG) that DHS had not done enough to ameliorate the overcrowding and address the deteriorating conditions.

In a recent report, the DHS OIG found squalid conditions in several detention centers for migrant families and children in Texas, including "serious" overcrowding, minors going without hot meals for days and detainees begging not to be returned to their cells.

Vice President Mike Pence went to U.S.-Mexico border last week to see a couple of the facilities for himself. He pushed back against Democrats' claims of a "manufactured crisis" and defended border agents. Still, after seeing the overcrowding in the facility in McAllen, Texas, he called it "tough stuff," and said, "When we have overflow, as we do in an overwhelmed system, the need for those temporary facilities is evident."