WASHINGTON — A Democratic lawmaker on Wednesday blamed the Trump administration's border policies for the deaths of migrant children, an accusation the acting head of the Homeland Security Department called "appalling."

The brouhaha came at a House Homeland Security Committee hearing on the budget for the sprawling law enforcement department, which has seen major upheaval over the past two months following a White House-orchestrated shake-up. Kevin McAleenan, the head of U.S. Customs and Border Protection, was named to lead the department temporarily following the resignation of Secretary Kirstjen Nielsen.

At the hearing, Rep. Lauren Underwood, D-Ill., questioned McAleenan about what he knew of the psychological problems migrant children face when they are separated from their parents. Last year, the administration separated more than 2,500 children from parents as part of a policy to prosecute anyone caught crossing into the United States illegally, but that practice was stopped. Border agents are still allowed to separate children at the U.S.-Mexico border if the adult has a criminal history or there is concern for the health and welfare of the children.

Underwood told McAleenan that "at this point, with five children dead and thousands separated, it's a policy choice being made by this administration, and it's inhumane."

McAleenan responded by calling that an "appalling accusation."

The committee's top Republican, Alabama Rep. Mike Rogers, accused Underwood of saying the administration was intentionally murdering children.

"I did not say murder," said the first-term lawmaker, who also is a nurse. "I said five children have died as a result of a policy choice."

The squabbling continued. After a brief recess, Republicans on the Democratic-run committee were able to push through a vote to admonish Underwood. Her statement was stricken from the official hearing record, and she was barred from talking during the rest of the session.

Chairman Bennie Thompson, D-Miss., said Underwood's statements were appropriate.

McAleenan testified that more money was needed to help manage the immigration crisis, where vast numbers of Central American families are entering the U.S., straining resources. There have been more than 100,000 border crossings per month the past two months, a 12-year high. The families crossing require different care from single adults and can't be easily returned over the border.

"We continue to face tragedies on the border," McAleenan said. He also cited the recent deaths of two teenagers and the drowning death of a 10-month-old baby who was on a raft trying to cross the Rio Grande with his parents when it overturned. Border Patrol agents pulled some of the group to safety.

Rep. Nanette Barragán, D-Calif., said the separation of families, and what she described as false claims by administration officials over the practice, and other border policies have helped foster the notion that what is happening is intentional.

"It's a belief based on all the lies that have been out in the public," she said.

She said McAleenan should not be proud of the work his agencies are doing.

"Look at all the lies. Look at all the harm done to children and their mental health. Look at the children that are dying under your watch," she said. "You should not be proud of a record of having five children die under your watch."

The U.S. government has faced months of scrutiny over its care of children it apprehends at the border. On Wednesday, Sen. Dick Durbin, D-Ill., and 23 other Democratic or independent senators asked International Committee of the Red Cross and homeland security's inspector general to investigate the conditions of facilities.

On Monday, a 16-year-old Guatemala migrant died after being held for six days — twice as long as federal law generally permits.

A 2-year-old child died last week after he and his mother were detained by the Border Patrol. The agency said it took the child to the hospital the same day the mother reported he was sick, and he was hospitalized for several weeks.

Another teenager died April 30 after officials at a Health and Human Services Department detention facility noticed that he was sick.

Two small children, ages 7 and 8, died in December in separate incidents. Following those deaths, Homeland Security ordered medical checks of all children in its custody and expanded medical screenings.