McALLEN, Texas (Border Report) — U.S. Customs and Border Protection on Thursday morning released migrant apprehension data from March, which showed total arrests increased 71% from February along the Southwest border, and a 100% increase in unaccompanied migrant children crossing the border from Mexico, most into South Texas.

More than 172,000 migrants were arrested along the Southwest border, CBP officials reported. So far this fiscal year, over 569,800 migrants have been encountered along the Southwest border, most from the Central American “Northern Triangle” countries of El Salvador, Honduras and Guatemala, as well as from Mexico, officials said.

And despite such a significant increase in apprehension rates, CBP officials say most are adults, not unaccompanied children or migrant families, crossing illegally into the United States. These adults are expelled back to Mexico under Title 42 guidelines, which remain in effect at least through April 21, to stop the spread of coronavirus between countries.

There were 18,890 unaccompanied migrant children apprehended in March — more than doubling February figures. The children made up about 11% of total arrests along the Southwest border but “they make up the largest demographic group of individuals in custody at CBP facilities,” according to the news release.

A group of unaccompanied migrant youth are seen on April 6, 2021, in La Joya, Texas, after being apprehended before dawn by U.S. Border Patrol agents. (Border Report Photo/Sandra Sanchez)

This is because all unaccompanied migrant children who are apprehended must, by U.S. law, be taken into custody and processed and turned over to officials with U.S. Health and Human Services. Processing the children — some barely older than toddlers — takes time as they question their age, home country and whether they have phone numbers or address for families or sponsors living in the United States they can contact.

HHS officials have been working inside the CBP migrant processing tent facility in the South Texas town of Donna to help expedite this process, but still CBP officials report they are overwhelmed with young children.

During a visit to the facility by Republican lawmakers from the House Judiciary Committee this week, lawmakers said there were pods in the Donna facility built to hold 52 kids that had over 500 children in them.

Ranking Committee Member U.S. Rep. Jim Jordan, of Ohio, said the lawmakers were told in the Donna facility that March “was the busiest month on record” in the Rio Grande Valley Sector. He added that “40% of manpower is currently used for processing illegal migrants.”

Border Patrol agents in the Rio Grande Valley have come across large groups of 100 or more migrants. Nearly 50 such groups have been encountered, so far in fiscal year 2021, totaling over 4,700 migrants, CBP officials said.

“The safety of our workforce, our communities, and individuals in our care is a top priority.  CBP personnel put themselves and their families at risk with every encounter at the border. Since the start of the pandemic, more than 8,300 CBP employees have tested positive for COVID-19, and 28 have passed away,” the news release said.