The Department of Homeland Security (DHS) says smugglers on the U.S.-Mexico border are using “recycling rings,” a process in which children are passed back across the border in order to help multiple adults gain illegal entry.

DHS Secretary Kirstjen Nielsen mentioned the practice Wednesday during a hearing with the House Committee on Homeland Security, stating, “The children are being used as pawns to get into our country.”

“We have encountered recycling rings, where innocent young people are used multiple times to help illegal aliens gain illegal entry,” she explained.

Current immigration law limits the length of time that family units can be held in detention at the border to 20 days, meaning these groups of illegal immigrants are usually released to the interior of the United States while they await court proceedings. In some cases, the children and “parents” in question are not even related — DHS separated 170 adult and child units between April 19 and Sept. 30 last year because the persons involved had no familial relation. (RELATED: DHS: 170 Fake Families Separated At Border)

“Smugglers and traffickers have caught on, realizing that the outdated laws, lack of resources, and bad court decisions effectively give them a free ticket to America,” Nielsen argued. “Information about the weaknesses in our system have spread quickly in Central America — in fact, they are advertised.”

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Former Acting Immigration and Customs Enforcement (ICE) Director Tom Homan confirmed that his agency has seen “the problem before” of children being used multiple times to help unrelated illegal immigrant adults gain entry to the U.S.

Homan told The Daily Caller that the “zero tolerance” policy preventing family separations has only further incentivized the use of children because they can no longer be held separately while their adult chaperones undergo immigration proceedings.

National Border Patrol Council President Brandon Judd explained to the Caller how smugglers and cartels profit by operating the “recycling rings.”

“From what I understand … the smuggling organizations or cartels have use of young children to pair with adults because they know family units will not be separated upon crossing the border illegally,” Judd said. “The use of children as pawns allows the cartels to recruit people to cross the borders illegally, thereby allowing them to generate profits.”

He added, “The cartels are a business, albeit an illegal business, and they must generate profits to remain in power. They’re constantly looking for ways to recruit people to cross the border illegally.”

Smugglers are able to get away with re-using children because border agents are not allowed to take fingerprints on any children under the age of 14 in order to record their data. As such, it is nearly impossible for agents to track children who come across the border outside of whatever identification is provided to them.

“The solution is getting biographic and biometrics data” on children who cross the border, Homan said, while Judd suggested the use of 90-minute DNA tests.

Judd claimed that ICE’s Homeland Security Investigations (HSI) unit is currently investigating cases involving the re-use of children to help adults gain entry. ICE did not immediately respond to a request for information on such cases.

The arrival of family units at the border has surged over the past year, with U.S. Customs and Border Protection (CPB) reporting that border agents have arrested 290 percent more family units in FY 2019 over FY 2018. Many of these units come from Central American countries and arrive in massive caravans, increasing the strain on border resources.

Overall, illegal arrivals are set to hit 1 million in FY 2019, Nielsen told Congress on Wednesday.

DHS did not immediately respond to a request for data on “recycling rings.”

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