The Trump administration reported on Tuesday, Oct. 8, that arrests made at the U.S.-Mexico border decreased again—the fourth consecutive month—lauding Mexican and Central American countries in their combined efforts in controlling migrants.

Roughly 1 million migrants were apprehended at the U.S.-Mexico border last year, the most in over a decade, new Customs and Border Protection (CBP) statistics show.

Acting CBP Commissioner Mark Morgan said at a press conference Tuesday at the White House that, due to illegal crossing numbers being at a record high this spring, nearly 1 million illegal aliens were arrested and deemed inadmissible for entry to the United States in the 2019 fiscal year, Reuters reports.

According to Morgan, slightly more than 52,000 illegals were either apprehended or encountered at the southwest border in September, a decrease of almost 65 percent from a peak in May of 144,000. The monthly total remains the highest September level since at least 2014, CBP statistics show.

“[B]y the end of the fiscal year, we will see numbers more than triple the record for family units arriving at the border, with over 500,000, and record number of unaccompanied minors,” acting Homeland Security Secretary Kevin McAleenan said in a remark on Monday.

Immigration, being a central issue for President Donald Trump, has required the administration’s further efforts to limit access to asylum and limit immigration, Reuters reports.

In September, the U.S. Supreme Court has overruled a lower court ruling that blocked a new asylum policy in select states along the southern border. The new policy, now in operation, denies asylum to anyone who passes through another country en route to the U.S. without seeking protection there first, AP News reports.

Morgan praised the Trump administration’s immigration policies, noting that the numbers reflected an “unprecedented achievement” in the face of overwhelming surges of asylum-seekers. He also spoke highly of the Mexican government for cooperating with the United States through President Trump’s “remain in Mexico” policy. The policy, enforced through Migrant Protection Protocols (MPPs), effectively requires any non-Mexican migrant who claims asylum at the southern U.S. border to remain in Mexico while their case goes under review.

Under MPPs, approximately 51,000 have been deported back to Mexico, where some had to wait for weeks or months in cities where living conditions aren’t ideal.

This alone, Morgan said, has served as a deterrent for asylum-seekers without basis, according to Courthouse News.

Morgan also noted that cooperative asylum agreements are being reached between the United States and El Salvador, Guatemala, and Honduras, Courthouse News reported. The same agreements would enable the U.S. government to send asylum-seekers currently at the border directly to one of the three countries.

As of September, 71 miles of new wall has been erected, though Morgan said that they are not considered “linear miles,” meaning that updates and other upgrades have been previously made where a barrier is already in place.

The Trump administration anticipates at least 100 new linear miles of wall be built by Dec. 31 and Morgan said he is expecting to see 450 miles to be reected by the end of 2020.