Border patrol agents arrested nearly 13,000 family members last month — the highest August total ever recorded, according to statistics released Wednesday.

That marks a 38 percent spike from July in “family units” that were apprehended, the latest data shows.

The increase comes after President Trump’s decision to back off the provision of his “zero tolerance” crackdown that separated children from parents in an attempt to deter illegal migration.

Department of Homeland Security officials said the arrival of so many families was due to court-imposed restrictions limiting the duration children may be detained in immigration jails.

“The numbers have continued to increase because this is a well-known avenue to arrive in the U.S. and be allowed to stay,” said Customs and Border Protection Commissioner Kevin McAleenan, calling the trend “a crisis of significant proportions, from a humanitarian perspective and a security perspective.”

Migration typically rises in August

Migration numbers typically rebound in August after a summer lull. Arrests of migrant family members increased by a similar percentage during the same period last year, rising 36 percent from July to August 2017. But the 12,774 family members taken into custody this August marked a threefold increase over 2017.

Agents working in South Texas described August as a busy month of rafts coming across the Rio Grande and groups so large they had to be loaded onto Border Patrol buses.

In addition to the number of families detained between official ports of entry, 3,181 family members attempted to enter from Mexico at U.S. border crossings, typically seeking asylum, according to Customs and Border Protection, which categorizes such migrants as “inadmissibles.”

Nearly all family members appearing at the border are from the Northern Triangle of Central America — Guatemala, Honduras and El Salvador — where homicide rates and grinding poverty have fueled emigration for decades.

What has changed, DHS officials say, is the growing recognition in Central America of the opportunities afforded by what they consider “legal loopholes” in U.S. enforcement. Restrictions on child detention leave the federal government powerless to stop parents who bring children, officials said.

By law, the government can hold children in immigration jails for up to 20 days. Such limitation, DHS officials say, hamstrings enforcement efforts and results in a system — they call it “catch and release” — that entices more and more parents to bring children northward along a dangerous path dominated by smuggling mafias.

“We have an increasingly vulnerable population in the hands of increasingly violent criminal organizations,” McAleenan said. According to Customs and Border Protection estimates, the journey to the United States from Central America costs $5,000 to $8,000, he said, generating $2 billion a year in profits for smugglers.

There is also concern the publicity generated by Trump’s family-separation strategy — and its abrupt reversal — may have had the unintended effect of encouraging more migration. Border agents who backed Trump’s crackdown say smugglers are telling potential customers that their window may close if the rules are tightened again.

The “zero tolerance” prosecution initiative that DHS and the Justice Department launched in May no longer applies to parents who arrive with children, but officials continue to impose criminal charges and potential jail time on single adults. Their declining share among the arrest totals is proof, DHS officials say, that more-aggressive enforcement has a deterrent effect.

DHS is mounting new legal challenges to child-detention rules in a bid to hold families for however long it takes to adjudicate their appeals for asylum or other forms of humanitarian protection offered by the U.S. immigration system.

‘More suffering’

Trump has cited migration surges in justifying his push for a border wall and in recent weeks has repeated threats to shut down the federal government this fall if lawmakers do not fund the project.

“A different administration would see this as a reason to reach across the aisle and come together on a long-term solution that has something for everyone, from asylum access to security, and addresses why Central Americans are fleeing. But that’s not going to happen,” said Adam Isacson, a security analyst at the Washington Office on Latin America, a human rights group.

“My fear is that this White House will use the increased numbers to cause more suffering among the migrant population and maybe to limit legal immigration further,” Isacson said.

Isacson said he did not view the jump in family arrests as a crisis yet, but he cautioned, “If the numbers continue to rise through the end of the year, as they did in 2016, by December the system for dealing with the asylum demand could be near collapse.”

Customs and Border Protection figures show the number of migrants under age 18 in U.S. custody also rose last month, and the Department of Health and Human Services said this week it had 12,800 minors in its shelters, a record number.

HHS said it plans to triple the amount of available beds it has at a tent camp in the desert outside El Paso to cope with the increase.

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