Fewer immigrants have been caught crossing the border this year, a sign that the number of illegal crossings is continuing to drop, officials said.

The continuous drop comes despite "historic levels of front-line personnel, technology, and infrastructure," at the border, according to a statement released Friday by Homeland Security Secretary Jeh Johnson.

More than 151,000 people have been stopped along the southwest border for the first half of the 2015 fiscal year, according to the agency, a 28 percent drop for the same time period last year.

According to the agency, the numbers "are a fraction," of the number of apprehensions when compared to 2000, and a continual marker that the number of people crossing the border has been dropping.