Over 300 South Korean employees, apprehended during an immigration sweep in the United States last week, returned to their homeland on a chartered flight and were joyously reunited with their families on Friday.

These individuals were part of the 475 people caught during the September 4th immigration operation at a battery production facility being built on Hyundai’s expansive car manufacturing site west of Savannah, Georgia.

Their detention, along with the release of U.S. footage showing some of these Korean workers restrained with chains on their wrists, ankles, and waists, has ignited public indignation and a feeling of betrayal in South Korea, a vital ally of the United States.

Upon the arrival of their charter flight at Incheon International Airport, located near Seoul, the workers appeared in the arrivals area, where high-ranking officials, including the presidential chief of staff Kang Hoon-sik, applauded their return.

“We feel sorry that we failed to bring them back home earlier, but we did our best,” Kang said.

Hundreds of media personnel crowded the airport to document their arrival, with many citizens enthusiastically shouting “Welcome back!” One demonstrator displayed a large banner featuring a picture of U.S. President Donald Trump alongside a message condemning U.S. immigration policies before security intervened. South Korea’s Foreign Ministry requested the media to obscure the workers’ faces in any footage and photographs from the airport, honoring the workers’ concerns about maintaining their privacy.

The plane carried 330 people who were detained in the Georgia raid – 316 of them are South Koreans, including a pregnant woman, and the rest are Chinese, Japanese and Indonesian workers. They had been held at an immigration detention center in Folkston, 285 miles (460 kilometers) southeast of Atlanta.

On the flight back home, Kang said the workers clapped and shouted with joy.

Relatives relieved after their loved ones were released

Families waited anxiously in a multi-level parking lot near the airport terminal. As the elevator doors opened, each group of workers stepped out to hurried embraces from their relatives.

Hwang In-song, the brother of one worker, told The Associated Press he had been unable to reach his sibling until midnight Thursday, when he finally received a text message from his brother saying he was safe. He said the past week was “the hardest time” for their family.

“We asked him if he was okay health-wise, and he said he was in good health. We didn’t get to talk much because he was about to board the plane,” Hwang said.

Choi Yeon-ju, the 64-year-old mother of another worker, said her son’s detention was “incredibly shocking and stunning.” But she said her son also finally made a short phone call to their family after midnight Thursday.

“He didn’t say much about how he was, just saying he was okay and telling us not to worry too much,” she said, waiting with her daughter-in-law and a grandchild.

Trump halted the workers’ departure process

South Korea said Sunday it had reached an agreement with the U.S. for the Korean workers’ releases.

The South Korean government originally sought to bring them back home on Thursday, but said the plan was shelved due to a reason involving the U.S. side. South Korea’s Foreign Ministry later said Trump had halted the departure process to hear from South Korea on whether the Koreans should be allowed to stay to continue their work and help train U.S. workers or should be sent back to South Korea.

South Korean officials said that one South Korean national who has relatives in the U.S. eventually chose to stay in the U.S.

The battery plant, a joint venture between Hyundai and LG Energy Solution, is one of more than 20 major industrial sites that South Korean companies are currently building in the United States.

Speaking at the airport, Kim Dong Myung, the chief executive officer of LG Energy Solution, downplayed concerns that the raid would cause major delays to the launch of the Georgia factory, saying disruptions “would be within a level we can manage.”

South Korea calls for change in US visa systems

U.S. authorities said some of the detained Korean workers had illegally crossed the U.S. border, while others entered legally but had expired visas or entered on visa waivers that prohibited them from working. But South Korean officials and experts have accused the U.S. of failing to act on its long-running request to improve a visa system to accommodate skilled Korean workers as the U.S. wants South Korea to expand U.S. industrial investments.

In reality, South Korean companies have been mostly relying on short-term visitor visas or Electronic System for Travel Authorization to send workers who are needed to launch manufacturing sites and handle other setup tasks, a practice that had been largely tolerated for years.

South Korean Foreign Minister Cho Hyun, who traveled to Washington to negotiate the workers’ release, said U.S. officials had agreed to allow them to later return to finish their work at the Georgia site. The two countries also agreed to set up a bilateral working group to create a new visa category to make it easier for South Korean companies to send their employees to work in the U.S., according to Cho’s ministry.

“We will discuss all measures, including creating a new visa category, establishing a new quota, and various steps to make obtaining a visa easier,” Cho told reporters as he returned to South Korea on Friday. He said most of the detained workers had short-term B-1 or B-2 visas and ESTAs.

South Korean President Lee Jae Myung on Thursday warned that South Korean companies will likely hesitate to make further investments in the U.S. unless it improves its visa system.

The raid was the latest in a series of workplace raids conducted as part of the Trump administration’s mass deportation agenda. But many South Koreans were stunned because the raid came about two weeks after a summit between Lee and Trump, and a little more than a month after South Korea’s announcement of a $350 billion investment plan in the U.S. in return for a lowered U.S. tariff rate.