“Certain children are being recycled, 4-, 8-, 10-year-old children.”

DNA tests revealed that 30% of all immigrant adults arriving at the southern border with children were not related to the children, according to a Saturday Washington Examiner report.

The tests, part of a pilot program being tried out by Immigration and Customs Enforcement, were used for only a few days earlier this month in McAllen and El Paso, Texas. According to an immigration official who spoke to the Examiner on condition of anonymity, the tests are meant to deter the growing number of migrants who lie about the children traveling with them at the border.

“There’s been some concern about, ‘Are they stepfathers or adopted fathers?'” the official, who was involved in the program’s rollout, told the Examiner. “Those were not the case. In these cases, they are misrepresented as family members.”

The tests, which are designed by a U.S. company, use a cheek swab to quickly verify the adult’s relationship to a child. According to the official, rather than submit to the test, some migrants admitted they were not related to the children traveling with them.

According to ICE, the Department of Homeland Security will now look over the results of the pilot program and decide if it will be rolled out as a comprehensive solution.

“This is certainly not the panacea. It’s one measure,” the official told the Examiner.

According to the official, the tests weren’t just useful in sussing out bogus relationships. When DHS officers were unsure of family relationships, they served as a useful tool to verify legitimate families as well.

The pilot program comes as border officials grapple with the growing problem of children being used by migrants to avoid a lengthy detention after attempting to enter the U.S. A group of Congressional Republicans learned during a visit to the border last month that hundreds of children are being “rented out” to accompany migrants crossing the border illegally.

Crossing the border with a child allows the person who illegally crossed to apply for asylum in the U.S., while a 2015 court ruling mandates that families not be held in custody for more than 20 days.

“They can utilize loopholes in the immigration law. These children don’t know. They take these one month trips — traversing through horrible, horrible conditions multiple times,” said Justin Kallinger, a border patrol spokesman. “Certain children are being recycled, 4-, 8-, 10-year-old children. They come with false documents from adults.”

Kallinger said agents face many obstacles when trying to ascertain the legitimacy of family relationships, most notably a lack of hard evidence.

“We have prosecuted as many as we can. We run into issues with evidence, intent, time in custody once it is found to be a fraudulent family unit are just a few of the barriers we face right now,” Kallinger said.

Attorney General William Barr also moved last month to end “catch and release” tactics at the border, denying bail to migrants who seek asylum after illegally crossing into the country. According to Barr, the move would help deter migrants from using children to take advantage of loopholes in U.S. law.