BROWNSVILLE, RGV – The ACLU has sued the Obama administration following the opening of the Department of Homeland Security’s new family detention center in Dilley, South Texas.

The group claims asylum seekers from Central America are being detained as an intimidation tactic to scare other undocumented immigrants from crossing into the United States.

Meanwhile, Mary Meg McCarthy, executive director of the National Immigrant Justice Center, has penned an op-ed in which she says new detention center for mothers and children “compounds national shame.”

The controversial Dilley facility, about 70 miles southwest of San Antonio, is projected to grow to be the largest in the country. It has an immediate capacity to detain about 450 mothers and children, but DHS plans to expand capacity to detain up to 2,400 by late spring 2015. DHS Secretary Jeh Johnson has already visited the 50-ACRE compound.

The Obama administration’s blanket no-release policy is a violation of federal immigration law and regulations, as well as the Fifth Amendment of the U.S. Constitution, which prohibit the blanket detention of asylum seekers for purposes of general deterrence, the complaint from ACLU charges.

“Locking up families and depriving them of their liberty in order to scare others from seeking refuge in the U.S. is inhumane and illegal,” said Judy Rabinovitz, deputy director of the ACLU’s Immigrants’ Rights Project, in a news release highlighting her group’s class action lawsuit.

“The government should not be using these mothers and their children as pawns. They have already been through devastating experiences, and imprisoning them for weeks or months while they await their asylum hearings is unnecessary and traumatizing.”

The ACLU lawsuit aims to “invalidate that policy and ensure that the families’ cases receive individualized reviews.” Asylum-seeking mothers and children are being detained at facilities across the country, the ACLU states, in places such as Karnes, Texas, and Berks County, Penn., and now Dilley.

“With the government’s opening of a huge new family detention facility in Dilley and plans to expand the capacity of the Karnes facility, Texas once again has the ignoble distinction of imprisoning more women and children than any other state,” said Adriana Piñon, senior staff attorney for the ACLU of Texas. “These families have already been determined by government officials to qualify for asylum proceedings, and many have family members ready to take them in. It is inexcusable to keep them locked up in prison-like conditions while they await their hearings.”

In her op-ed, the NIJC’s McCarthy said she is “deeply disappointed” in the opening of the new lockup in Dilley. McCarthy said the vast majority of mothers and children who will be “warehoused in Dilley” came to the United States—usually presenting themselves to Border Patrol agents—because they were forced to flee rampant violence in Central America.

“During fiscal year 2014, more than half of individuals entering family detention facilities were children, including many infants and toddlers. Detention is particularly harmful for children and survivors of violence, who frequently suffer psychological trauma and mental health issues. Family detention centers are located in remote places where access to legal counsel is minimal, even though it is critical to helping asylum seekers navigate our complex immigration system to get life-saving relief from deportation,” McCarthy wrote.

Rather than locking up mothers and children, the U.S. government should release them on cost-effective, humane alternatives to detention, which cost as little as 70 cents to $17 per person per day compared to the projected daily cost of detention at Dilley of $298 per person, McCarthy said.

“Many of the mothers and children who have fled to the United States have family here who are ready to take them in and help them heal from trauma as they await their asylum hearings. While Secretary Johnson touted a new in-country refugee application process for certain Central American children who have family in the United States, his suggestion that such a limited program is a silver bullet that solves the protection needs of all those in imminent danger is disingenuous and wrongly perpetuates the myth that women and children arriving at our borders do not have legitimate protection needs of their own.”

McCarthy added that detaining mothers and children is “misguided, inhumane, and a waste of taxpayer dollars.” She pointed out that President Obama recently reminded Americans that “we were once strangers too,” and called upon Americans this holiday season “to reflect on those who are strangers in our midst and remember what it was like to be a stranger.”

“Detaining families is not in line with American values. NIJC calls on President Obama to treat all families humanely and end the use of family detention before more children and mothers are harmed,” McCarthy added.

During his visit to Dilley, DHS Secretary Johnson said: “This must be clear: Our borders are not open to illegal migration.”