Overview

• Interior ministry said more than 50% of network devices and 99% of key security devices are back in operation, with 551 systems being tested for restart and 96 presumed damaged, including mobile ID and postal services.
• The blaze started with a lithium‑ion UPS battery explosion during relocation work in a fifth‑floor room, triggering thermal runaway and destroying nearly all battery packs there.
• Firefighting ended at 6 p.m. Saturday after roughly 22 hours, with crews submerging removed batteries to prevent reignition; one worker sustained first‑degree burns.
• The government raised its information‑systems alert to the highest level, prioritized HVAC repairs before server restarts, and pledged to restore postal and financial services first while extending deadlines for filings.
• Authorities opened a formal probe into the cause and damage, noting suppression was complicated by the concentration of critical systems at the Daejeon site and by limits on using water near servers.