MISSION, Texas  (NewsNation Now) — Shocking new images show hundreds of immigrants being detained under a bridge near the Texas border.

The pictures were snapped at the temporary processing site under the Anzalduas International Bridge.

The footage comes just a day after a top border patrol union official warned agents have had to release some migrants who’ve tested positive for COVID-19 into the United States.

Meanwhile new reporting says that the number of unaccompanied children detained at the border likely hit an all-time high in July.

Several lawmakers have been highly critical of the Biden administration’s border response saying they are not doing enough to address the crisis. They feel like immigration policy right now is on the backburner and they want Vice President Kamala Harris removed from her role overseeing things and someone else put in charge.

“I’ve asked the administration very respectfully, what is the endgame? What is the endgame on this? And I don’t know, they know the answer,” said Rep. Henry Cuellar, a Democrat representing south Texas.

Cuellar says more than 3,000 people were apprehended Sunday in the Rio Grande Valley.

Data show illegal border crossings are at a 21-year high. Last month alone, nearly 200,000 people attempted the dangerous trek.

“Something has to change when it comes to border immigration issues,” Cuellar said.

Republicans are calling the border crisis a catastrophe.

Texas Senator Ted Cruz tweeted that it’s a true disaster and a revolving door that migrants are taking advantage of.

Colorado Rep. Ken Buck adding that it’s outrageous.

Some organizations, like the Federation of American Immigration Reform (FAIR), are pushing for a crackdown on policies.

“How can we ask our border patrol to go out and do this job,  if the government isn’t supporting the whole process to make sure people aren’t encouraged to try to run around the border patrol,” said FAIR president Dan Stein.

Pro- immigration groups are working just as hard. On Monday, a group of them are restarting litigation to block Title 42, an order that lets U.S. officials send migrants back to Mexico without the chance to seek asylum or other protections.

Title 42 is a public health law and was put in place last year as a COVID-19 precaution and the White House says as of right now they don’t have a timeline on when they will lift it.