Brownsville, Texas (CNN) Democratic Reps. Ben Ray Luján and Joaquin Castro on Monday called on President Donald Trump to visit the South Texas border and witness the separation between immigrant parents and children.

"Mr. President, if you really are in charge, pick up the phone and stop this," Luján told reporters in Brownsville, Texas. "The President should come visit these children."

Castro, of Texas, echoed the New Mexico lawmaker's call, telling reporters a little later: "He should do as Ray Luján said and come see the children for himself."

The comments came at a roundtable moderated by Democratic Rep. Filemon Vela of Texas that included Democrats Luján, Castro, House Homeland Security Committee ranking member Bennie Thompson of Mississippi, Rep. Sheila Jackson Lee of Texas,and Rep. Frederica Wilson of Florida.

The discussion came after the lawmakers toured two facilities holding children, Casa Padre and Casa Presidente, in Brownsville, which are Southwest Key facilities where unaccompanied and separated children are being held.

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