The U.S. government picked-up nearly 19,000 children traveling unaccompanied, some as young as three, along the southern border with Mexico in March, according to the Associated Press. Authorities said it was the largest monthly number ever recorded.

The U.S. Border Patrol encountered 18,663 unaccompanied children for March, well above the 11,475 in May 2019 and 10,620 in June 2014. The March numbers are roughly double the encounters by the Border Patrol in February and five times more than in March 2020.

The surge comes as President Joe Biden reversed many of his predecessor’s strict immigration policies. The Biden administration has exempted unaccompanied children from pandemic-related powers, instead, releasing them to “sponsors” in the U.S., usually parents or relatives, while being allowed to pursue their cases in backlogged immigration courts.

The surge of unaccompanied minors and families has strained border holding facilities, which aren’t allowed to hold people for more than three days but often do.

A number of factors have led to the recent surge, including changes in U.S. immigration policies, the 2020 coronavirus pandemic, the economic declines in Central America countries and the damage from two destructive hurricanes that slammed Guatemala and Honduras last year.

Meanwhile, border agents expelled nearly a third of migrant parents and children traveling together and caught at the southwestern border last month, Reuters reports. 

At a news conference at the White House on March 25, President Biden said that the “vast majority” of families encountered at the border were being sent back.

“We’re trying to work out now, with Mexico, their willingness to take more of those families back,” Biden said.

Around 17,000 of nearly 53,000 parents and children caught at the border in March were expelled under a coronavirus public health order.

Texas child welfare officials are investigating reports of abuse allegation and neglect at an emergency facility holding more than 1,600 migrant teens at the Freeman Coliseum in the city of San Antonio, Al Jazeera reports. 

One of the more serious allegations includes sexual abuse, though no other details were provided.

Other allegations include insufficient staffing, children not eating and those who tested positive for COVID-19 not being separated from the population, Texas governor Greg Abbott said in a press conference.

The Republican governor has been a vocal critic of the Biden administration’s handling of the situation at the U.S. southern border, saying the facilities should be shut down and children be move to better-staffed and secured locations.

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