The blaze likely began with an explosion of a battery at the National Information Resources Service in Daejeon city, about 85 miles (130 kilometers) south of the capital Seoul, at around 8:20 p.m. local time on Friday, the news agency reported.

That led to a “thermal runaway” releasing extreme heat in the server room, making it difficult for firefighters to contain the inferno, officials told the agency. Prime Minister Kim Min-seok said the fire had “paralyzed” the government’s internal digital platform, shutting down its official email system and several websites. More than 600 online government services and systems remained down on Saturday morning, including a mobile ID system and online postal services.

Kim warned that airport travelers who depend solely on mobile IDs could also face disruption, according to local media. Around 170 firefighters and 63 fire trucks hurried to the scene on Friday, with the main blaze under control by 6:30 a.m. the following day, reports said. One worker reportedly suffered first-degree burns to the face and arm while handling batteries, with almost 200 lithium-ion battery packs destroyed in the room, according to Yonhap news agency. (CNN)