EL PASO (CBSDFW.COM/AP) — U.S. immigration authorities are using a Texas Border Patrol station to test a program meant to speed up reviews of asylum claims, offering a glimpse of how the Trump administration may enforce its partial asylum ban.

The pilot project, called the “Prompt Asylum Case Review” system, began October 7 in El Paso, with a goal of having a decision by an immigration judge within 10 days, according to a senior Department of Homeland Security official who spoke on condition of anonymity because details of the program have not been made public. Mexicans are exempt.

The rollout has not been publicly announced, leading to complaints by attorneys that they have no access to clients and are left in the dark.

“The most concerning part here is we have not received any official word from Border Patrol and it seems to be purposeful that they have not told the (non-governmental organizations) what’s going on,” Linda Rivas, executive director of Las Americas Advocacy Center, said in a conference call Monday with reporters.

Taylor Levy, an immigration attorney in El Paso, said lawyers cannot enter Border Patrol holding centers, which are designed to keep people no more than 72 hours. She learned about the pilot from an attorney who was unable to reach her two clients, both women from El Salvador with infants who crossed the border Oct. 8.

An immigration judge denied their appeals by phone meaning the judge couldn’t see documents including proof of death threats they faced in El Salvador. One woman has been deported and another is waiting to be sent home.

The pilot is designed to give asylum seekers 24 hours of access to a phone in a private room before an initial asylum screening, but attorneys said the rules are unclear and that they received no notice or instructions. If asylum seekers fail the screening, they can appeal to judges in Otero, New Mexico, by phone.

Its launch comes as the administration expands another effort to address a surge in asylum seekers: sending them back to Mexico to wait while their cases wind through U.S. immigration courts. Homeland Security said Monday that it extended its “Migration Protection Protocols” policy — also known as “Remain in Mexico” — to Eagle Pass, Texas, its sixth location. The U.S. says more than 55,000 people have been made to wait in Mexico since the policy was introduced in January.

Asylum seekers who are returned to the Mexican border city of Ciudad Acuna from Eagle Pass will be scheduled for court in Laredo, Texas, a drive of more than three hours. The Laredo facility is inside a tent on Customs and Border Protection property, with a video link to a judge sitting in San Antonio.

The pilot program in El Paso, if expanded, may prove to be a critical tool in the administration’s efforts to enforce a ban on asylum for anyone who passes through another country before reaching the U.S. border with Mexico. The partial asylum ban, which took effect last month, appears largely aimed at Central Americans, Cubans and Africans, who have contributed to making the U.S. the world’s most popular destination for asylum seekers. Mexicans and unaccompanied children are exempt from the ban.

The administration has struck agreements to send asylum seekers subject to the ban to Guatemala, El Salvador and Honduras to have their cases heard there, but officials acknowledge those countries lack adequate infrastructure.

The asylum seekers confirmed by lawyers to be in the trial are being held at a Border Patrol station that grew from small office building to a sprawling maze of tent camps and new construction this year amid of surge of asylum seekers, many of them Central American families.

The station can hold up to 500 migrants, said Border Patrol spokesman Ramiro Cordero. Brown army-style tents hastily put up in the spring have since been taken down, as apprehensions in the agency’s El Paso sector have plummeted from nearly 1,000 a day in the spring to around 200.

A Customs and Border Protection spokesman said Monday that because the detainees appear by phone, they could be in any Border Patrol facility in the El Paso sector, which includes New Mexico and West Texas.

Homeland Security confirmed the existence of the pilot program on Thursday, hours after it was reported by The Washington Post, but provided few details. It called the program a joint effort with the Justice Department, which runs immigration courts, to expedite proceedings at a single location while providing protections and due process for all. The statement said it would be enforced on single men and people traveling in families who are subject to the asylum ban.

🗣️Seeking asylum is a human right. And Trump is doing everything he can to infringe upon that right. Under this program, asylum-seekers have one day to call a lawyer and can’t even meet with them in person. It completely abandons due process. https://t.co/meQcEU0TfR — Ilhan Omar (@IlhanMN) October 27, 2019

Critics have relied on scarce details in news reports to pan the pilot program. U.S. Rep. Ilhan Omar, a Minnesota Democrat, tweeted Sunday that it “completely abandons due process.”

El Paso was also testing grounds for the administration’s widespread practice of separating families at the border as part of a “zero tolerance” policy to criminally prosecute every adult who crossed the border illegally, including those who came with their children.

The government made no public announcements about the El Paso experiment on family separations. Levy, then-legal coordinator for Annunciation House in El Paso, said in a court filing last year that she noticed a “significant increase” in clients who were separated from their children during that time, but the government didn’t tell immigration attorneys until Oct. 24, 2017 that its new policy was to separate parents whose children were over 10 years old. The government didn’t formally announce its “zero tolerance” policy until April 2018.

© Copyright 2019 CBS Broadcasting Inc. All Rights Reserved. The Associated Press contributed to this report.)