The South Korean prosecution formed an investigative team of at least three prosecutors to look into a food poisoning scandal after a complaint was filed against McDonald’s Korea, an undercooked patty of which allegedly sickened a 4-year-old. 

According to the Seoul Central District Prosecutor’s Office, the investigators are soon to summon officials from the country’s biggest fast food chain to look into whether they violated food safety rules.

The move came several days after a family filed a complaint saying that their daughter developed hemolytic-uremic syndrome and lost 90 percent of her kidney function after consuming a burger from a McDonald’s outlet in Pyeongtaek, Gyeonggi Province, in September.

HUS, also known as “hamburger disease,” is from bacteria in contaminated foods such as undercooked hamburger patties. McDonald’s Korea, however, has denied responsibility for the incident, although it said it would cooperate fully with the investigation.

With the help of medical experts, the investigative team has reportedly been working on determining the cause of the victim’s illness and any possible links to the hamburger.

By Bak Se-hwan (sh@heraldcorp.com)