Almost 1 million migrants were arrested at the Mexico border this past year

Migration across the southern border is reportedly like nothing the Department of Homeland Security has seen before.

U.S. border authorities arrested more than 975,000 people during the 2019 fiscal year, The Washington Post reports via Trump administration data released Tuesday. That's an 88 percent increase from the previous year, culminating in "numbers no immigration system in the world is designed to handle," U.S. Customs and Border Protection Acting Commissioner Mark Morgan said Tuesday.

The number of border arrests in fiscal year 2019, which ended Sept. 30, marks the highest total since 2007. The largest annual number of arrests ever still sits at 2000's total of 1.6 million, but this recent influx was still just as difficult for border agents to handle, DHS officials say. That's because earlier migrants were largely "single adults from Mexico who could be quickly processed and deported," the Post writes. Today, migrant groups include huge numbers of Central American parents with children who are actually looking to surrender to U.S. border agents and claim asylum.

With border authorities unprepared for these changing demographics, migrants and children are increasingly being kept in overcrowded and unsanitary conditions, sparking condemnation from lawmakers and full-on lawsuits. The Trump administration has since tried to curb this surge by pushing Mexico to step up border enforcement on its side and making controversial agreements with Central American countries that bar people who travel through them from claiming asylum in the U.S. Those asylum bans with El Salvador, Guatemala, and Honduras go into effect this week, Morgan said Tuesday.