A fire broke out around 8:20 p.m. on the 26th in lithium-ion batteries for uninterruptible power supply (UPS) at the National Information Resources Service in Daejeon. Fire authorities have been carrying out suppression efforts past midnight. Lithium-ion batteries can experience a "thermal runaway" phenomenon in which embers explode at high temperatures. In such cases, it is not easy to put out a fire due to flames and smoke.
The National Information Resources Service is an agency that manages the government's and local governments' IT (information and communications) systems. Fire authorities initially tried to suppress the blaze with carbon dioxide extinguishers out of concern for data loss. The flames later reignited, and they decided to deploy water.
Earlier, one employee suffered first-degree burns to the face and arm in the fire. About 100 people in the office evacuated. According to the Ministry of the Interior and Safety, 70 government computer systems, including mobile ID and the National Complaint Portal, were affected. The ministry issued the "alert" level of the crisis warning.