Authorities also captured 8,897 unaccompanied minors — a slight decrease from 8,973 the month prior — as well as 31,606 single adults, compared to 30,653 in March.

The total apprehension number is the highest since April 2007, at the height of Mexican mass migration to the United States, when CBP apprehended 105,825 people.

Apprehension and turn-away numbers are generally used as a metric for illegal immigration inflows into the United States.

But Central American migrants, unlike their predecessors, are prone to voluntarily surrendering to American authorities in order to initiate asylum claims.

Still, the massive surge in border apprehensions has overwhelmed CBP — which mans ports of entry — as well as Border Patrol, which is in charge of securing areas between those ports.

Border Patrol Chief Carla Provost told the Senate Judiciary Committee on Wednesday that care for migrant families and minors is hampering the agency's security role.

"I joined the Border Patrol nearly 25 years ago because of my strong belief in our border security mission," said Provost.

"I could never have envisioned that today agents would spend at least 40 percent of their time as child care professionals, medical care givers, bus drivers and food service workers," she added.

The Trump administration has sought to tighten border controls and interior enforcement as a response to the sustained flow of Central American asylum-seekers.

And the administration is asking for billions in emergency border funding to compensate for the border agents' increased humanitarian workload.

A senior administration official said Tuesday the White House is pushing forward changes to asylum procedure, giving a wider berth for border agents to prejudge the validity of asylum claims.

Rep. Jesús García (D-Ill.) criticized the move Wednesday, saying that "allowing people to make their claim … has been the American way and we should return to that."

"There is a humanitarian crisis. It can be dealt with in a humane and orderly way," García added.

Updated at 5:10 p.m.