Immigrations and Customs Enforcement is taking over more than 1,600 beds from the U.S. Bureau of Prisons to temporarily handle an increase in undocumented immigrants being detained by the agency, ICE officials said Thursday. Among the facilities being used by ICE is a 230-bed prison camp near El Paso.

The increase in detention space comes at a time when apprehensions of undocumented immigrants have returned to levels seen toward the end of the Obama administration.

“Due to the current surge in illegal border crossings and implementation of the U.S. Department of Justice’s zero-tolerance policy, U.S. Immigration and Customs Enforcement (ICE) is working to meet the demand for additional immigration detention space, both long and short term,” ICE spokeswoman Danielle Bennett said in an email. “To meet this need, ICE is collaborating with the U.S. Marshals Service (USMS), the Bureau of Prisons (BOP), private detention facility operators and local government agencies.

“To meet the immediate need, ICE has entered into inter-agency agreements with BOP to acquire access to more than 1,600 additional beds at BOP facilities. The use of BOP facilities is intended to be a temporary measure until ICE can obtain additional long-term contracts for new detention facilities or until the surge in illegal border crossings subsides,” Bennett said. “ICE continues to enforce immigration laws consistent with the Administration’s directives and the law.  This includes ensuring sufficient detention space to hold aliens prior to removal or adjudication by an immigration judge.”

A Bureau of Prisons spokesperson said they have the space. “The BOP has a long history of supporting immigration enforcement efforts dating back to when the Immigration and Naturalization Service was a part of the Department of Justice. The BOP has bed space available due to the decline in the inmate population over the past several years, and will use existing staff to accomplish this mission,” the statement said.

ICE identified five prison facilities that will be used to hold immigration detainees. The largest is 1,000 beds at the federal prison complex in Victorville, California. The next largest is 230 beds in the Federal Correctional Institution La Tuna system based in Anthony, Texas, just west of El Paso. Other facilities being used are 209 beds at the Federal Detention Center SeaTac in Seattle; 130 beds in Sheridan, Oregon; and 109 beds at the Federal Correctional Institution Phoenix in Arizona.

Many of the prison complexes have multiple facilities. La Tuna, which houses about 1,300 inmates, has a main prison and adjacent camp in far west El Paso County, as well as what is called a “federal satellite low” camp on Fort Bliss near El Paso. ICE spokeswoman Leticia Zamarripa said ICE would house detainees at the Fort Bliss camp, which had been housing 136 federal prison inmates in military-style barracks, according to the La Tuna website.

Attorney General Jeff Sessions last month announced that the Trump administration was implementing a new “zero tolerance” policy that requires criminal charges against anyone caught entering the country illegally. Previously, most people suspected of illegal entry were placed immediately in a civil deportation process.

One effect of the policy will be to slow the deportation process. Those apprehended by the Border Patrol now go through a criminal process, usually for the misdemeanor of entering without inspection. That process takes at least two to four weeks, with most misdemeanor defendants then pleading guilty before a federal magistrate and being sentenced to time served. Only then do they enter the deportation process, which can take anywhere from days to years, depending on circumstances.

President Trump made controlling the border a priority of his 2016 campaign. Apprehensions of illegal crossers, which had been declining for years, dropped even more sharply in the first months of the Trump administration. But over the last three months, they have risen back to levels seen at the end of the Obama administration. The apprehension numbers are still well below numbers seen a decade ago under both the Georg W. Bush and Obama administrations.

In May, Border Patrol agents apprehended just over 40,000 suspected illegal crossers along the Southwest border, including more than 26,000 in the agency’s five Texas sectors. In May 2017, Border Patrol apprehensions in the Southwest totaled 14,500, including 8,900 in Texas. In May 2016, apprehension totals were just over 40,000 in the Southwest and 27,000 in Texas. The Obama administration didn’t seek extra detention space when apprehension rates were comparable to what we’re now seeing. But that reflected the changing face of migration. Mexico had been the primary country from which immigrants came, but that flow began to slow and was eventually replaced by Central Americans, many of whom were seeking asylum, which slows down the deportation process and creates demand to house them.

Even as apprehensions of illegal border crossers have largely declined in recent years, the number of immigrants detained by ICE has risen. Bennett, the ICE spokeswoman, said the agency has housed an average of 41,134 detainees a day so far this fiscal year, compared to 38,106 in fiscal year 2017. In fiscal year 2016, the last full year of the Obama administration, ICE reported detaining 34,260 people per day. In fiscal year 2008, the end of the Bush administration, the number was 31,771.  ICE has said it costs about $130 a day to house a detainee.

Longtime El Paso County judge Veronica Escobar, who is now the Democratic nominee for El Paso’s congressional seat, said the plan to put detainees in prison spaces is another example of flawed immigration policy by the Trump administration.

“While the number of border crossings and apprehensions continues to ebb and flow annually, the numbers are still at historic lows.  But what is climbing—significantly, and seemingly, with no end in sight—is both the amount of money the Trump administration is spending as well as the level of cruelty it’s applying in its approach.  Between separating families, betraying DREAMers, increasing detention, and demanding tens of millions for a border wall, the financial and human costs should be deeply alarming to the American public,” Escobar said.