The number of Latin American migrants crossing the southern border increased this August compared to last August, boosting the total migrant inflow to more than 240,000 since 2011.

According to Border Patrol’s apprehension data, a cross-border flow of 4,632 “unaccompanied minors” and 5,158 people in “family units” was recorded arrested last month. The Associated Press notes that is a 52 percent increase over last August’s total of 6,424 people.

The flow of migrants had, until the late summer, been lower than the 2014 surge when Border Patrol tracked the arrival of 62,977 youths — some of whom likely are adults older than 18 — plus 62,848 people in “family units” — largely from El Salvador, Guatemala, and Honduras. President Barack Obama allowed his deputies to release the vast majority of the migrants into the United States to join their extended families, file for work permits, and enter U.S. schools.

The total for the two years — not counting the September 2015 inflow — will be 203,319 migrants. In 2011, 2012, and 2013 an additional 34,984 Central American youths crossed the border. That’s a five-year total of at least 243,303 migrants.

If they win their court cases, they’ll be put on a fast-track to citizenship. Since the Latin-American migration slowly began in 2011, only a very small proportion of the successful migrants have been sent home.

As president, Obama has the authority to quickly return the migrants without allowing them to file court cases.

Amid the huge public protest in 2014, Obama pressed Mexican officials to curb the expected 2015 inflow. That tactic has been partly effective in regulating the inflow and also in muting public protest.

By the end of August in 2015, another 35,494 youths and 34,565 people in family groups — mostly women and girls — had successfully crossed into the United States. That adds up to 70,059 additional migrants, or more than half the 2014 inflow of 135,825 migrants.

Customs and Border Protection acknowledges the increase in apprehensions to ABC News but noted that the total numbers compared to last year’s total surge are lower.

“In August, U.S. Customs and Border Protection experienced an increase from the month of July in the number of unaccompanied children and family units apprehended,” a Customs and Border Protections spokesperson told ABC News. “Overall, the number of Unaccompanied Alien Children (UAC) apprehensions in 2015 remains significantly lower compared to the number of apprehensions through August of last year, with a 46 percent decrease.”

White House Press Secretary Josh Earnest addressed August’s increase in apprehensions Monday calling the spike during the hot month of August “surprising” and “concerning.”

“[W]e take this issue very seriously, and we’re going to continue to be engaged in both trying to stem that flow but also messaging very clearly to the people in Central America who may be thinking about trying to help their child get into the United States, to urge them not to subject their child to that dangerous journey,” Earnest said.