Posted with permission from Daily Caller News Foundation

Arrests of illegal aliens along the U.S.-Mexico border ticked up again in August, the fourth consecutive month that apprehensions have risen since declining to recent lows in the early months of the Trump administration.

Border agents arrested or turned away more than 30,000 illegal immigrants last month, up 22 percent compared to July, according to Customs and Border Protection figures released Monday. The total for August was nearly double the 15,700 apprehensions along the southwest border in April.

Border arrests are used as a proxy for overall levels of illegal immigration. The idea is that, assuming a given standard of border security, more apprehensions mean that more illegal aliens are slipping undetected into the U.S., and vice versa.

The rising number of arrests along the border, which typically fall during the hot summer months, suggests that President Donald Trump's early deterrent effect on illegal immigrants may be wearing off.

Still, illegal immigration flows across the border are likely far lighter now than they were at the same time last year under the Obama administration. Border apprehensions were 41 percent lower in August compared to the same month last year, and year-to-date totals for FY 2017 are 24 percent lower than the same period in FY 2016, according to CBP figures.

A potentially worrying trend is that much of the recent rise in illegal immigration is driven by an influx of unaccompanied children (UAC) and family units. Those cases are particularly troublesome for immigration authorities because they often trigger complex appeals in immigration courts.

While all border arrests climbed 22 percent from July, apprehensions of UACs and family units jumped 30 percent.

UAC and family units represented 34 percent of all Border Patrol arrests along the southwest border in August, and 32 percent of all inadmissible aliens turned away at points of entry.

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