Congressional delegations offered competing explanations for the recent rise in migration during visits to the U.S.-Mexico border, with Democrats calling for more humane treatment of migrants while Republicans accused the Biden administration of allowing “open borders.”

On Friday, a group of House Democrats led by former Congressional Hispanic Caucus chairman Joaquin Castro, D-Texas, stressed the need to fix the U.S. immigration system after visiting a facility for unaccompanied migrant children in Carrizo Springs, Texas.

“We’re here today to find solutions,” Castro said at a news conference, one of several held by lawmakers at the border in recent weeks. “We’re here today to go back to Washington and offer recommendations for how this process can be improved, how the asylum process can be approved and how people’s human rights can be respected.”

Democrats point to natural disasters and economic strife in Central America as a primary driver of migration, emphasizing migrants’ rights under U.S. law to seek asylum at the border.

“Being here and listening to these kids, hearing their stories, their hopes and aspirations, is a reminder that this isn’t about politics, this isn’t about playing games,” said Rep. Ilhan Omar, D-Minn., whose family fled war in Somalia when she was a child. “It’s about the humanity of these children.”

Republican lawmakers took a starkly different stance, arguing that President Joe Biden’s policies have undermined a border that was more secure under the Trump administration.

“The Border Patrol agents that we were riding with said that under the Trump administration policies, things were working right. It was the best it had ever been,” said Sen. Mike Braun, R-Ind., in a video recorded around midnight Thursday. He was one of 18 senators on a trip that included a late-night patrol trip with border agents.

[GOP delegation slams Biden for ‘crisis’ during border visit]

Republicans also blamed Mexican drug cartels, which charge thousands of dollars to transport migrants to the border.

“I was here two years ago, and it bears no resemblance. We were controlling the border,” added Sen. Thom Tillis, R-N.C., standing in front of a camp of migrants underneath a bridge between the U.S. and Mexico. “Now we’re hearing that Border Patrol is spending more time helping these families while criminals are bringing drugs and illicit materials into the United States.”

Border crossings in recent months are on track to hit record levels, with U.S. Customs and Border Protection recording around 100,000 crossings in February, including more than 9,000 unaccompanied children.

Those numbers are rapidly increasing. A senior U.S. Border Patrol official told reporters Friday that over the past 30 days, CBP has encountered an average of 5,000 migrants daily.

The increase in unaccompanied migrant children has also strained government systems.

More than 5,000 children were in CBP custody and nearly 12,000 were in Department of Health and Human Services custody as of March 24, according to the most recent data released by HHS and DHS.

Most single adults and some families are turned away at the border under a Trump-era public health directive, but unaccompanied minors and many families with young children are permitted to stay. Images of migrant children in cramped, makeshift conditions at the border have increased the pressure on the Biden administration, and Congress, to offer solutions.

“What we saw and the conversations we had will help inform the decisions we are going to make,” said Rep. Pete Aguilar, D-Calif. “We all agree that this is a broken immigration system that was compounded by the decisions that the prior administration made.”

[As more migrant children arrive, Biden faces political hurdles]

Democrats in Congress have largely backed the Biden administration’s approach, which involves rapidly setting up new HHS intake centers to manage the influx of unaccompanied children who by law should not remain in CBP facilities for longer than 72 hours. They also are hoping for a comprehensive bill to overhaul the immigration system, although prospects of such legislation are unclear because of slim Democratic majorities in the House and Senate.

Rep. Veronica Escobar, a Texas Democrat whose district includes El Paso, is scheduled to lead a delegation to the border on Saturday with nine colleagues, including one Republican: freshman Rep. Victoria Spartz of Indiana, a Ukrainian-born lawmaker.

Escobar told reporters Friday that she invited on the trip “select Republican members, with a focus on Republican members who didn’t vote to overturn the results of the election.”

“I feel like they are people who I am hoping we can work with and work together to focus on solutions,” she said. “I’m so delighted that my colleague, one of my Republican colleagues, accepted.”

Escobar said the group will tour a CBP processing facility and an HHS shelter for unaccompanied children and plans to speak with Border Patrol agents, migrant children, immigration lawyers, humanitarian advocates and nongovernmental organizations.

Escobar called the remarks that Republican senators made during their border visit “completely predictable.” She faulted them for slamming the Biden administration’s handling of the border Republicans failed to “bring any ideas to the table” when they controlled both congressional chambers and the White House.

“Unfortunately, anytime we see more individuals, families, children arriving at our front doorstep than normal or than predictable, there’s a rush to call it a ‘crisis,’ and the same situation plays out year in and year out,” she said. “Republicans call for more ‘border security,’ Democrats call for immigration reform. Republicans say, ‘We’ll only do immigration reform if we do more border security.’”

But as border communities have become more “militarized,” immigration reform “becomes more elusive,” she said.