REYNOSA, Mexico — Juliana Gonzales is a close observer of migrant foot traffic on the Texas-Mexico border; she makes a living washing cars as they wait to cross the international bridge into the United States.

And lately, she's noticed a change: a big booth perched at the bridge's halfway point, where U.S. Customs and Border Protection agents are stopping and turning away asylum-seekers.

"They cross running really fast, but then they get stopped," she said. And then they wait.

"Sometimes they stay there [on the bridge] sleeping," Gonzales added.

The Texas Tribune thanks its sponsors. Become one .

Agents have been standing on various international bridges at least since June, a practice that coincided with the Trump administration's "zero tolerance" policy to prosecute immigrants crossing the border illegally. That policy led to hundreds of children being separated from their families, creating a national uproar and a suspension of the policy.

But the booth is a new twist. Customs and Border Protection (CPB) officials confirm that they've installed the booth, surrounded by orange cones, halfway across the McAllen-Hidalgo International Bridge so agents can stop travelers before they make it to the official port of entry on the U.S. side. CBP spokesman Rick Pauza wrote in an email to The Texas Tribune that the structures were placed on the bridge between four and six weeks ago as a way to maintain the “flow of legitimate trade and travel." He added that there are no similar midpoint booths at other South Texas ports of entry.

“Keeping illicit goods and people out of the country and managing the influx of Central Americans seeking asylum requires a careful balance of our resources and space,” Pauza said. “CBP is taking a proactive approach to ensure that arriving travelers have valid entry documents in order to expedite the processing of lawful travel.”

Jodi Goodwin, an immigration attorney in Harlingen, said she believes the new midpoint booth on the bridge is about more than "managing" migrants; it serves to “prevent people from stepping onto American soil so that they could ask for asylum.”

“The point there was to discourage [migrants coming] to the points of entry to be able to ask for asylum,” Goodwin said. “We’ve never had any agents stationed at the middle of the bridge.”

The new procedure tracks with the Trump administration’s efforts to crack down on asylum, which has limited the chance for migrants to pursue such claims.

The Texas Tribune thanks its sponsors. Become one .

It’s not illegal for migrants to seek asylum at ports of entry — indeed, it's a primary avenue for doing it. The Trump administration encouraged migrants to present themselves at ports of entry this summer, instead of illegally crossing the Rio Grande.

But that encouragement came as CBP began stationing agents at the midpoint of various border bridges in South Texas this summer. Asylum-seekers were told that there was no space for them in the port of entry facilities and they should come back another time — which forced immigrants to either seek shelter on the Mexican side or keep waiting on the bridges.

In June, some asylum-seekers interviewed by the Tribune waited on the bridge in Brownsville for nearly a week, their children sleeping next to them, before they were allowed to cross.

Patricia, a Reynosa resident who routinely crosses the U.S.-Mexico border with her daughter to shop at a flea market in Hidalgo — she declined to provide her last name in order to keep crossing without incident — said lines of migrants waiting to seek asylum with their children were getting longer this summer.

Since the CBP booth, agents and cones showed up at the bridge's halfway point, she said, little by little, “they don’t come this way anymore.”

Elsa Cavazos contributed to this report.

Editor's note: The Texas Tribune and TIME have partnered to closely track the family separation crisis at the U.S.-Mexico border. This story is not available for republishing by a national news organization until Oct. 2 at 6 a.m. Texas news organizations may run it at any time. For more information email nchoate@texastribune.org.