More military personnel head to the US-Mexico border as officials describe an increase in migrant crossings

The Defense Department is ramping up resources at the US-Mexico border as officials describe a surge in border crossings in places including Eagle Pass, Texas, where the mayor has declared a state of emergency.

Some 800 new active-duty personnel are being sent to the border, where 2,500 National Guard members already are serving, Department of Homeland Security officials announced Wednesday night in a call with reporters.

The move comes as migrant crossings along that border are rising, surpassing 8,600 over the last 24 hours, according to a Department of Homeland Security official. That's up from around 3,500 daily border arrests after the expiration in May of Title 42 triggered new consequences for those who cross the border illegally. There were than 8,000 apprehensions on Monday.

The busiest sectors are Del Rio, El Paso, Lower Rio Grande Valley, and Tucson - each facing more than 1,000 encounters over the last 24 hours, according to the official. Eagle Pass is in the Del Rio sector.

On Wednesday, a 3-year-old boy died as his family attempted to cross the Rio Grande near Eagle Pass, according to a statement from the Texas Department of Public Safety.

The DPS Tactical Marine Unit was alerted that a child was swept away by the current while trying to cross the river with his family just after 3:30 p.m. local time.

Troopers transported the child to shore, and he was pronounced dead at a local hospital, according to DPS, which said the death occurred north of the marine barrier in Eagle Pass.

The influx has strained federal resources and overwhelmed already-crowded facilities, officials have said.

Officials gave no clear explanation for what has prompted the latest surge and said they're still working through specific reasons. They continued to identify disinformation from smugglers, poor economies, authoritarian regimes and the climate crisis as forces driving migration.

Many who leave their homes for the United States face long and dangerous treks in hopes of finding better, safer lives. Some may flee violence, while others may immigrate for economic opportunities or to reunite with family, experts say. Deteriorating conditions in Latin America exacerbated by the coronavirus pandemic also have contributed to the influx of migrants into the US.

Recent court filings have underscored the challenges administration officials face in receiving the increased number of people arriving at the border, including crowded processing areas leading to children being temporarily separated from their parents.

Since President Joe Biden took office, officials have set up additional soft-sided facilities similar to tent complexes to process the growing number of migrants crossing the border, but those facilities are not equipped to provide long-term care.

Around 3,000 migrants crossed into the US near Eagle Pass on Wednesday alone, a source familiar with the situation told CNN. Hundreds waited in the city of around 28,000 about 150 miles southeast of San Antonio for transport to a processing facility and were moved out quickly, the source said.

Maverick County Sheriff Tom Schmerber told CNN Thursday he believes cartels are helping drive the current surge of migrants in Eagle Pass, the county seat.

"I mean they're making money with the immigrants. They're making money with the drugs," Schmerber said.

"I know this because we have smugglers coming from Houston, Florida, Austin - everywhere to pick up these immigrants. There's a connection there."

About 2,700 migrants crossed into the US near Eagle Pass on Tuesday, followed by another 3,000 on Wednesday, according to the sheriff.

"It's something very strange. Never thought I was going to see something like that in Eagle Pass," said Schmerber, an Eagle Pass native.

Schmerber said the border town doesn't have the facilities to sustain the influx. He called for a zero-tolerance policy to curb the surge.

"It means you're arrested, processed, and deported right back to your country, just like that," Schmerber said. "There's no such thing from the federal government saying zero-tolerance. They're accepting immigrants."

Biden administration officials have been grappling with a growing number of Venezuelans arriving to the US southern border. Frosty relations with Venezuela make it difficult for the US to remove those nationals arrested at the border, posing a unique challenge for officials.

Schmerber, a Democrat, accused the Biden administration of sending a message that the border is "going to be open."

"Some people are drowning. Some people are dying," Schmerber said. "Some of those ranchers are finding bodies or bones. So why take a risk? Why make those people come like this?"

On Thursday, a group of roughly 100 migrants from Venezuela stuck on the banks of the Rio Grande told CNN they were not willing to go back to Mexico because it was "too dangerous."

After crossing the river earlier, the group was stuck on the riverbank in Eagle Pass when rows of concertina wire prevented them from proceeding.

The migrants stood in the water and shouted through the wire, saying they had been robbed and attacked in Mexico. They said they wanted to wait on the banks until US authorities let them in. The group said they had been there for hours trying to figure out how to turn themselves in to federal authorities.

One migrant told CNN they were willing to wait even if it meant they would be deported. Some told CNN they had been trying to enter the US via the legal process of requesting asylum and have waited months to get through the online application process.

Eagle Pass Mayor Rolando Salinas Jr. declared a state of emergency Tuesday, citing a "severe undocumented immigrant surge" into Eagle Pass.

"The City of Eagle Pass is committed to the safety and well being of our local citizens. The emergency declaration grants us the ability to request financial resources to provide additional services caused by the influx of the undocumented immigrants," Salinas said in a news release without providing specifics on the number of migrants encountered.

US Customs and Border Protection is temporarily suspending vehicle processing operations at a crossing in Eagle Pass "in order to redirect personnel to assist the US Border Patrol with taking migrants into custody," the agency announced in a statement Wednesday.

"In response to this influx in encounters, we will continue to surge all available resources to expeditiously and safely process migrants," Customs and Border Protection said in the statement. "We will maximize consequences against those without a legal basis to remain in the United States."

Border authorities in Eagle Pass processed the large influx of migrants on Wednesday in an "orderly way" but warned the administration will "impose consequences" on as many people as possible who crossed, Department of Homeland Security officials said. Consequences could include expedited removals and other penalties available under the Title 8 process.

The US military has long provided support to the Department of Homeland Security (DHS) on the border and a surge of personnel to the area is not unprecedented, or unexpected, amid strains on federal resources. Troops have generally served in a support role rather than enforcement. Military personnel will not have direct contact with migrants, according to a Department of Defense spokesperson.

The up to 800 additional personnel will, for 90 days, "fill critical capability gaps, such as ground-based detection and monitoring, data entry, information analysis, transportation, and supply chain support, until DHS can address these needs through contracted support," the spokesperson said in a statement. "This deployment is consistent with other forms of military support to DHS over many years."

In May, ahead of the expiration of the Covid-era Title 42 restriction, US Customs and Border Protection encountered more than 8,000 people daily and had around 25,000 migrants in custody, raising alarm within the Biden administration.

CNN's Ray Sanchez, Karol Suarez and Brad Parks contributed to this report.