An Oklahoma Congressman who visited an Army base being used to house illegal immigrant children now wonders what the federal government is hiding after he was denied access to the facility.

“There is no excuse for denying a Federal Representative from Oklahoma access to a federal facility in Oklahoma where unaccompanied children are being held,” Rep. Jim Bridenstine said in a statement following his visit Tuesday to Ft. Sill Army base near Lawton.

The Department of Health and Human Services has set up housing at Ft. Sill and two other military bases – Lackland Air Force Base in San Antonio and Ventura County Naval Base in Oxnard, Cali. – to house thousands of unaccompanied alien children, or UACs, who were apprehended at the southern U.S. border.

Bridenstine went to Ft. Sill to observe the conditions under which the 1,200 UACs there are living and to find out to whom they would be released.

But when he showed up at the facility, Bridenstine says he was told by a guard with a security unit which calls itself the “Brown Shirts” that he could not observe the children or their living conditions.

When the congressman spoke to a manager and HHS official, he was told he would have to schedule a formal visit for July 21.

“Any Member of Congress should have the legal authority to visit a federal youth detention facility without waiting three weeks,” Bridenstine said in his statement.

Though unable to get inside the facility, Bridenstine described its exterior.

“A new fence has been erected by HHS, completely surrounding the barracks and covered with material to totally obscure the view,” he said, adding that “every gate is chained closed.”

“What are they trying to hide?” Bridenstine asked. “Do they not want the children to speak with Members of Congress?”

The heavy security and limited access Bridenstine observed appears to be common at other HHS facilities. Besides using military bases to house UACs, HHS is exploring other non-military facilities throughout the country.

Fox News reported that staffers with the Baptist Family & Children’s Services, who call themselves the “Brown Shirts” on account of their tan t-shirts, stand watch at the Lackland camp. A counselor at the base there called the atmosphere “submissive” on account of the guards, who forbid contact between the immigrant children and outsiders.

And as The Daily Caller reported last month, HHS created an atmosphere of secrecy when it placed numerous restrictions on members of Congress and staffers who were invited to tour the UAC facility at Ventura County Naval Base. The agency barred attendees from speaking to the children or staff or from taking any pictures. (RELATED: Obama Admin Forbids Lawmakers From Taking Photos Of Illegal Immigrant Facility)

According to the latest official figures, 52,000 UACs and 39,000 parents with children have been apprehended at the border. That number is nearly double the flow of immigrants compared to the same time last year.

The UACs are being transported to Ft. Sill and other facilities because, rather than turning the children away at the border, U.S. immigration policy requires that they be put into the care of HHS while they await deportation proceedings. HHS seeks relatives or sponsors for the UACs. It is unclear what percentage of UACs are returned to their home countries.

Requests for comment submitted to HHS and to Baptist Family & Children’s Services were not returned.

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