Last week, over 300 South Korean workers caught in an immigration sweep in the US returned home, arriving on a charter flight. They were joyfully reunited with their families on Friday.

The raid, which occurred on September 4, involved about 475 people at a battery factory being built on Hyundai’s extensive auto plant site, located west of Savannah.

Images from the US, displaying some Korean workers bound with chains at their wrists, ankles, and waists, have sparked wide public anger and a feeling of betrayal in South Korea, a vital ally of the US.

After their charter plane, a Boeing 747-8i from Korean Air, landed at Incheon International Airport, just west of Seoul, they appeared in an arrivals hall, with senior officials including presidential chief of staff Kang Hoon-sik clapping hands. One hugged Kang.

Hundreds of journalists gathered at the airport to cover their arrival. One protester unfurled a huge banner with a photo of President Donald Trump and a message criticizing US immigration crackdowns before security officials persuaded him to stop.

The South Korean Foreign Ministry asked media to blur the workers’ faces in video and photos at the airport, citing requests by the workers who worried about 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 southeast of Atlanta.

The workers’ release provided relief to their families and colleagues, some of whom came to the airport to meet them.

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 saying his brother 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 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, adding her son’s detention was “incredibly shocking and stunning.”

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

The South Korean government had pushed to bring them back home on Thursday, but said the plan was shelved due to a reason involving the US side.

South Korea’s Foreign Ministry later said President Donald 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 US workers or should be sent back to South Korea.

“President Trump had directed that the (detainees) should be allowed to return home freely and those who didn’t want to go didn’t have to,” South Korean President Lee Jae Myung told a news conference Thursday. “We were told that, because of that instruction, the process was paused and the administrative procedures were changed accordingly.”

Lee said that one South Korean national who has relatives in the US eventually chose to stay in the US.

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.

They include other battery factories in Georgia and several other states, a semiconductor plant in Texas, and a shipbuilding project in Philadelphia, a sector Trump has frequently highlighted in relation to South Korea.

US authorities said some of the detained Korean workers had illegally crossed the US 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 US of failing to act on its long-running request to improve a visa system to accommodate skilled Korean workers as the US wants South Korea to expand US 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.