JACUMBA HOT SPRINGS, Calif. — A group of migrants from China surrendered to a Border Patrol agent in remote Southern California as gusts of wind drowned the hum of high-voltage power lines, joining others from Ecuador, Brazil, Colombia and elsewhere in a desert campsite with shelters made from tree branches.

Their arrival Wednesday was another sign that agents have become overwhelmed in recent days by asylum-seekers on parts of the U.S. border with Mexico. In tiny Eagle Pass, Texas, nearly 6,000 migrants crossed from Mexico in to the U.S. in two days, prompting authorities to close one of the town’s two official border crossings so those agents could instead help with the influx. Border crossings have closed recently for similar reasons in San Diego and El Paso, Texas.

After a dip in illegal crossings that followed new asylum restrictions in May, President Joe Biden’s administration is again on its heels. Democratic mayors and governors are seeking more relief for hosting asylum-seekers and Republicans are seizing on the issue ahead of 2024 elections.

The Homeland Security Department said Wednesday it would grant Temporary Protected Status to an estimated 472,000 Venezuelans who were in the U.S. on July 31, easing paths to work authorization. That’s in addition to 242,700 Venezuelans who already had qualified for temporary status.

The administration is also sending 800 active-duty military troops to the border, adding to 2,500 National Guard members there. It’s expanding border holding facilities by 3,250 people to nearly 23,000, and extending home surveillance nationwide for families awaiting initial asylum screenings.

The administration renewed pressure — and blame — on Congress, which has long failed to agree on comprehensive changes to the nation’s immigration system. The Biden administration is now asking Congress for $4 billion in emergency funding.

Homeland Security said in a statement that it was “using the limited tools it has available to secure the border and build a safe, orderly, and humane immigration system.”

Theresa Cardinal Brown, the Bipartisan Policy Center’s senior advisor for immigration and border policy, said it’s normal to see a dip in illegal crossings after changes like those imposed in May, but that is usually short-lived once migrants see how things play out.

“People see what happened to the last group of people that tried and they’re like, ‘Oh, well maybe it’s not as harsh as they say,'” Brown said.

An increase in families arriving at the border led to unacceptable conditions in two of the busiest Border Patrol sector, a court-appointed monitor reported to a federal court last week. Dr. Paul H. Wise said children as young as 8 years old were separated from parents during processing in South Texas, a practice that has been mainly used for boys 13 to 17.

U.S. Customs and Border Protection said it was reviewing Wise’s report, noting limited, temporary separations may occur during processing for safety reasons but they are nothing like the long-term separations under former President Donald Trump. Wise said even short-term separation can have “lasting, harmful effects.”

In Eagle Pass, a town of 28,000 people, about 2,700 migrants crossed Tuesday and 3,000 Wednesday, according to Maverick County Sheriff Tom Schmerber. Mayor Rolando Salinas declared the city a disaster area on Tuesday.