It is reported by Ronhap.
It is specified that the incident occurred when about 800 students took part in the inauguration ceremony of the new head of the school.
During the event, teens smelled gas in the audience. Soon after, they began to complain of nausea and poor health.
It is clarified that most of the hospitalized were released home after providing them with first aid.
In May 2018, 13 people were injured in a chlorine gas leak at a plant in South Korea.