Until Thursday morning, hundreds of thousands of Haitians were legally living and working in the United States, along with thousands of Syrians. Now, their work permits are set to expire and their deportation protections will be terminated, throwing them in legal limbo.

The abrupt change in fate stems from the Supreme Court decision which found that the Department of Homeland Security had broad discretion in determining when to extend or terminate a form of humanitarian relief known as Temporary Protected Status.

It was a major victory for the Trump administration and its mass deportation pledge. And while the case was focused on the roughly 350,000 Haitians and 6,000 Syrians who have TPS protection, its repercussions stand to affect hundreds of thousands of additional nationals from 11 other countries. The shockwaves will be felt throughout the communities where they live and the industries in which they work.

“It would be the largest dedocumentization event of people in US history,” said Ahilan Arulanantham, who argued the Syrian TPS case before the Supreme Court and is a law professor at UCLA School of Law.

In a 6-3 decision, the court said lower courts had no ability to overrule DHS’s decisions on the TPS designation, which allows nationals from certain countries that are experiencing humanitarian or natural crises to legally live and work in the US as long as the TPS designation is valid.