CNN
Now playing
01:07
Lawmakers to Trump: End separation practice
ice explainer van jones vpx_00014806.jpg
ice explainer van jones vpx_00014806.jpg
Now playing
01:49
Why Democrats call for ICE to be abolished
 Yazmin Juarez and Marlee.
Arnold & Porter
Yazmin Juarez and Marlee.
Now playing
01:59
Child dies weeks after ICE custody
Maria Venegas
Now playing
02:36
ICE agents detain man driving wife to hospital
CNN
Now playing
01:39
Tlaib: We had border security before ICE
mother daughter reunited 62 days orig js_00003102.jpg
mother daughter reunited 62 days orig js_00003102.jpg
Now playing
01:13
Mother and daughter reunited after 61 days
WCVB
Now playing
00:58
Elizabeth Warren: US immigration a moral crisis
CNN
Now playing
01:45
Immigration attorney represented 3-year-old
CNN
Now playing
01:34
Lawmaker arrested during Trump protest
CNN
Now playing
01:24
Senator: US is encouraging illegal immigration
CNN
Now playing
01:44
Protesters block bus at immigration site
CNN
Now playing
01:55
Rep. Speier: I saw children crying in cells
US President Donald Trump walks to board Marine One as he departs for North Dakota at the White House in Washington, DC, on June 27, 2018.
NICHOLAS KAMM/AFP/Getty Images
US President Donald Trump walks to board Marine One as he departs for North Dakota at the White House in Washington, DC, on June 27, 2018.
Now playing
01:59
Trump blasts movement calling to abolish ICE
Secretary of State Mike Pompeo listens as President Donald Trump speaks during a cabinet meeting at the White House, Thursday, June 21, 2018, in Washington. (AP Photo/Evan Vucci)
Evan Vucci/AP
Secretary of State Mike Pompeo listens as President Donald Trump speaks during a cabinet meeting at the White House, Thursday, June 21, 2018, in Washington. (AP Photo/Evan Vucci)
Now playing
01:36
Trump: GOP should stop wasting time on immigration
Immigrant children walk in a line outside the Homestead Temporary Shelter for Unaccompanied Children, a former Job Corps site that now houses them, on Wednesday, June 20, 2018, in Homestead, Fla. (AP Photo/Brynn Anderson)
Brynn Anderson/AP
Immigrant children walk in a line outside the Homestead Temporary Shelter for Unaccompanied Children, a former Job Corps site that now houses them, on Wednesday, June 20, 2018, in Homestead, Fla. (AP Photo/Brynn Anderson)
Now playing
01:54
Children in limbo after Trump executive order
CNN
Now playing
02:08
Why immigrants make dangerous journey to US
(CNN) —  

Chain link fences, mattresses on the floor and families queuing to be processed – and oftentimes separated. These are the photos of the processing detention center in McAllen, Texas, that the Customs and Border Protection agency wants you to see.

More than 1,100 immigrants – including children – were being held at McAllen when reporters were allowed in Sunday.

Dozens of protesters stood outside the center as reporters and democratic lawmakers arrived to learn more about the facility where the Department of Homeland Security is processing and detaining immigrants accused of illegally crossing the border.

The lawmakers came to south Texas, they say, to learn more about the agency’s processing of undocumented immigrants entering the United States, including a Trump administration policy to refer all people who cross the border illegally for criminal prosecution on top of immigration proceedings.

As a result of enforcing that policy, families who cross illegally have been separated from their children because those accompanying the children are put into the criminal justice system.

Though media was able to tour the facility Sunday, they were barred from taking any pictures or video. CBP cited privacy concerns as the reason.

The agency released a handful of government images for publication – showing McAllen through the lens of those controlling it.

US Customs and Border Patrol

Democratic Sen. Jeff Merkley of Oregon, who first visited the South Texas border on June 3, described his second visit as more coordinated for Customs and Border Protection officials who gave the tour.

“We did see the children who were held inside here,” he told CNN’s Ana Cabrera in an interview.

“In wire-mesh, chain linked cages that are about 30x30, a lot of young folks put into them. I must say though, far fewer than I was here two weeks ago.

“I was told that buses full (of children) were taken away before I arrived. That was one of my concerns, that essentially, when you have to give lengthy notice, you end up a little bit of a show rather than seeing what’s really going on in these centers.”

US Customs and Border Patrol

The warehouse-like facility has holding pens made from chain-link fences on the inside separating the immigrants.

Mattresses with thermal blankets were strewn on the floors.

US Customs and Border Patrol

Federal officials said the immigrants were only being processed and wouldn’t be here longer than three days, but lawmakers reported they’d been told by immigrants within the facility that they had been there for seven.

US Customs and Border Patrol

Customs and Border Protection provided CNN with a document titled “Next Steps for Families” during the walk-through.

The document lists several steps for those in the government’s custody and includes several actions for people to take under the question “how do I locate my children,” including telephoning agency call centers and hotlines or emailing them.

CNN’s Dianne Gallagher reported that families are brought through the warehouse and separated by the adults’ gender, and that one woman approached CNN, crying and expressing fear about what would happen next.

US Customs and Border Patrol

The group of lawmakers included Sen. Chris Van Hollen of Maryland, Texas Reps. Filemon Vela, Vicente Gonzalez, and Sheila Jackson Lee, Vermont Rep. Peter Welch, Rhode Island Rep. David Cicilline, and Wisconsin Rep. Mark Pocan.

Speaking after visiting McAllen several Democrats expressed anger at the family separations and called on the Trump administration to change its policy.

“When you have a mother tell you directly that she’s in fear that she will never see her child again, and when the United Nations Human Rights Commission indicate to the Trump administration that you are violating human rights, then you know that what we are saying today is President Trump, cease and desist,” Jackson Lee said.

CNN’s Daniella Diaz and Eli Watkins contributed to this report.