SEOUL, South Korea — The chairman of one of South Korea’s biggest dairy companies has resigned after his company was accused of deliberately spreading misinformation that its yogurt help prevent COVID-19.

Hong Won-sik and other members of his family will still retain their commanding share of Namyang Dairy Products.

“I express my sincere apology for causing disappointment and anger to our country’s people with the Bulgaris-related controversy at a time when the nation is undergoing a hard time because of COVID-19,” Hong said Tuesday, tearing up.

Namyang financed research it aggressively promoted through the media and a symposium last month which claimed that its “Bulgaris” yogurt drinks were proven as effective in lowering risks of coronavirus infections.

Namyang’s stock prices temporarily rose before South Korea's Ministry of Food and Drug Safety sued the company for false advertising, saying that the research was dubious and never involved any animal testing or clinical trials.

Police searched Namyang’s Seoul headquarters last week. Namyang’s CEO, Lee Kwang-bum, has offered to resign.

Hong said he would take “all responsibility” by stepping down as chairman. He promised not to pass on management rights to his children, which is a much-criticized traditional practice at South Korea’s family-owned businesses.