Migrants seized or deemed 'inadmissible' down 18% in June

July 6 (UPI) -- The number of migrants deemed inadmissible to the United States or apprehended at the border fell 18 percent last month, U.S. Customs and Border Protection said.

CBP detained more than 34,000 migrants between ports of entry on the Southwest border in June, compared to 40,338 in May. The decline corresponds to a historical downward trend for this time of year, officials said.

"CBP is continuing to monitor sustained levels of illegal immigration, which is especially hazardous this time of year as the number of rescues by the U.S. Border Patrol continues to increase along with the temperature," the Department of Homeland Security said.

In all of 2017, CBP said it apprehended more than 300,000 individuals -- compared to almost 409,000 in 2016.

The agency deemed inadmissible another 8,451 who showed up at border ports in June. The designation includes those who are denied legal entry, those who seek humanitarian protection and others who retract their entry application and return to their home country.

Homeland Security spokesman Tyler Houlton said the decline owes to President Donald Trump's "zero-tolerance" policy on illegal immigration.

"As we have said before, the journey north is dangerous and puts individuals in the hands of smugglers and traffickers," he said. "We continue to call on Congress to address the crisis at the border by closing legal loopholes that drive illegal immigration."

Lindsay Toczylowski, executive director of the Immigrant Defenders Law Center, told NBC News many of the migrants crossing the border in May and June fled violence in Central America.

"They're not looking at what the Trump administration is doing in terms of zero tolerance policies when they make that decision to cross the border," Toczylowski said. "All they're thinking about is whether or not they can save the lives of themselves and their children."