(CNN) — Preliminary data indicates that US Border Patrol arrested around 51,000 people on the US-Mexico border in August, according to a Border Patrol source familiar with the data.
The August numbers show a consistent decline in arrests since the spring and come as the Trump administration has pushed forward numerous controversial policies intended to help stem the flow of migrants arriving at the southern border. An influx of migrant families and children, predominantly from Central America, strained resources along the border as severe overcrowding took hold earlier this summer.
Border Patrol apprehensions, a measure of illegal crossings, dropped around 30% from 71,999 in July to around 51,000 in August, according to the preliminary data.
Homeland Security acting Secretary Kevin McAleenan on Wednesday, appearing alongside President Donald Trump in the White House, said that preliminary border statistics indicate “a reduction of over 50% from May to today.” The statistics will be released early next week.
The August numbers mark a significant decrease since the high in May of more than 130,000 arrests, but it still remains higher than any month in the past two fiscal years. Many migrants arriving at the southern border turn themselves into Border Patrol after arriving on US soil.
Politico first reported on the August apprehension numbers. Customs and Border Protection, which releases monthly border arrest numbers, does not comment on preliminary data.
McAleenan on Wednesday also praised “continued partnership with Mexico,” regional support from Central American countries to combat irregular migration as well as enhancing security at the border.
Trump added, “The wall is being built. It’s going up rapidly.”
The administration has replaced and revamped sections of wall, but as of August no new miles of wall had been built where none previously existed.
Trump also thanked Mexico for its efforts to reduce illegal migration to the US border, claiming that “they have 25,000 soldiers right now protecting our border and they’ve done a fantastic job.”
Last month, the Trump administration informed Congress of plans to shift at least $155 million from the Federal Emergency Management Agency disaster relief fund to support its policy of returning some migrants to Mexico to await their immigration court proceedings in the US.
Defending the administration’s move to reprogram FEMA funds to the US-Mexico border even in the midst of Hurricane Dorian, Trump on Wednesday said, “We need help on the border, the numbers are really good.”
On Tuesday, Secretary of Defense Mark Esper authorized the diverting of $3.6 billion in military construction funds for 11 wall projects on the southern border with Mexico, according to defense officials and a letter from Esper to the Senate Armed Services Committee.
The move was immediately slammed by lawmakers. Senate Minority Leader Chuck Schumer called the decision “a slap in the face” to service members.
Last month, acting CBP Commissioner Mark Morgan said that, while the situation was improving, “we are still in a full-blown crisis,” referring to the high number of arrests in July.
A US Border Patrol official last month said a combination of factors contributed to the drop in arrests this summer, including Mexico’s enforcement efforts and the continued rollout of the Migration Protection Protocols, whereby migrants are returned to Mexico to await their immigration proceedings.
“All of these things together (are) helping” the official said.