According to Kuster, the delegation was invited to the region by U.S. Reps. Vicente Gonzalez and Filemon Vela, both Texas Democrats, whose districts include the border cities of McAllen and Brownsville, respectively.

Many of the lawmakers who traveled to the Lone Star State are part of a House caucus called the Democratic Working Women’s Group, Kuster said, describing members as mothers and grandmothers. She said she and other Democrats have a duty to bear witness to the situation unfolding on the border.

In recent weeks, more than 2,300 children have been separated from their families under the Trump administration’s “zero tolerance” immigration policy.

The policy, which calls for the prosecution of all individuals who illegally enter the country, was announced by U.S. Attorney General Jeff Sessions in early April.

Under the policy, any child traveling with a parent referred for prosecution has been placed in the custody of the Office of Refugee Resettlement, an agency within the U.S. Department of Health and Human Services.

The practice of separating children from their parents sparked an outcry from Democrats and many Republicans, including former First Lady Laura Bush, who called the practice cruel and immoral.

But supporters of the “zero tolerance” policy say undocumented immigrants are putting themselves in this situation by bringing their kids to the border in the first place. Sessions has argued the measure is a necessary corrective to what he perceives as lax immigration policies under the Barack Obama administration.

Last week, President Donald Trump made a sudden reversal, signing an executive order to end the separation of families and instead detain parents and children together for an indefinite period of time.

The executive order has resulted in significant confusion over how the more than 2,000 children who have already been separated from their parents will be reunited with them. Moreover, the order does not specify where families will be detained.

As an added complication, a 1997 consent decree known as the Flores settlement stipulates that unaccompanied minors can be held for only a short time before they must be released to a parent, legal guardian or other relative.

The U.S. Department of Homeland Security said in a news release Saturday that there is a coordinated process in place to reunite families and that the government knows the location of all the kids in its custody.

According to the release, more than 500 unaccompanied minors who were separated from their parents as a result of the “zero tolerance” policy have already been reunited with their families.

Kuster said she saw little evidence of those reunification efforts on Saturday’s tour.

Describing a U.S. Immigration and Customs Enforcement detention facility in Port Isabel, Texas, near Brownsville, Kuster said she and other lawmakers met with about 40 mothers who had been separated from their children.

According to Kuster, many of the mothers were from Honduras and spoke tearfully about the separation, as well as the violence they were fleeing. One of those women had been at the facility since May 25, Kuster said.

“It had been a month since she last saw her four children,” Kuster said. “She had no idea where they were.”

The delegation also visited a Customs and Border Protection processing facility in McAllen, which Kuster described as a large, prison-like warehouse with tall, chain-link fencing dividing people by age and sex.

She said many of the younger children were shivering and huddled beneath silver, Mylar blankets, unaccustomed to the air conditioning and trying to find relief from the bright, overhead lights.

Kuster said the Customs and Border Patrol staff that she and her colleagues spoke with were trying to be compassionate but found themselves in an impossible situation.

“When we asked about reunification, they said they need further guidance,” she said. “They did not have any direction as to how to go about reunification.”

Kuster, who is running for re-election, said she has received close to 1,000 calls, letters and emails from her constituents about the crisis on the border.