Sept. 8 (UPI) -- President Donald Trump on Sunday sent a warning to countries that have manufacturing plants in the United States to "please respect our Nation's Immigration Laws."

"Your Investments are welcome, and we encourage you to LEGALLY bring your very smart people ... and we will make it quickly and legally possible for you to do so," Trump said on Truth Social. He said he expected overseas firms to "hire and train American Workers."

Many Koreans, though, continue to be dismayed by the actions of one of their nation's longtime political and strategic allies. There were 475 workers arrested during the Thursday raid at a factory in Georgia, which Hyundai Motor Group and LG Energy Solution operate. Most of the workers detained were from South Korea.

The Thursday raid was announced by the Bureau of Alcohol, Tobacco, Firearms and Explosives and included officers from other agencies, such as Homeland Security Investigations and U.S. Immigration and Customs Enforcement.

It marked one of the largest immigrant raids in modern American history, and it was not immediately clear why the ATF participated in the crackdown.