El Paso, Texas — The long white tents, visible to anyone driving across East El Paso, Texas, are designed to be part of the biggest immigration holding facility in U.S. history, with a capacity for as many as 5,000 immigrants.

"That's what it is, a giant tent city," Democratic Rep. Veronica Escobar of Texas, who has been inside twice, told CBS News. "...There are hard floors. There are walls that go up, probably about three-quarters of the way to the ceiling."

Escobar said she saw about 1,500 people inside during her last visit two weeks ago.

The government awarded Acquisition Logistics a $1.24 billion contract to build and operate the detention center, dubbed by Immigration and Customs Enforcement as Camp East Montana, which opened last month.

A house in suburban Richmond, Virginia,

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