On the 28th, officials from the fire department, police, and the National Forensic Service are moving to conduct a joint inspection at the site of the fire at the National Information Resources Service (NIRS) in Yuseong-gu, Daejeon. On the 26th, a fire involving lithium-ion batteries for an Uninterruptible Power Supply (UPS) broke out at the NIRS, which houses government computer systems, causing a large-scale disruption to government digital services. Yonhap News.

The police have launched a full-scale investigation to determine the cause of the fire at the National Information Resources Service (NIRS), which led to the paralysis of government computer networks.

On the 28th, the Daejeon Metropolitan Police Agency began a joint inspection at the NIRS in Yuseong-gu, Daejeon, alongside fire authorities and the National Forensic Service.

The police continued the inspection for the second consecutive day, following the initial containment declared by fire authorities the previous day.

Kang Jae-seok, Chief of the Forensic Science Division, explained, "We promptly secured and requested an analysis of evidence during yesterday's on-site inspection," adding, "Today, we plan to conduct an extensive joint inspection to determine the exact cause of the fire."

The police secured and sent some components of the facility for analysis the previous day. They plan to send the batteries, which were removed from the server room and submerged in water tanks, to the National Forensic Service for analysis after a stabilization period of two to three days to discharge residual electricity.

The inspection, which began this morning, has continued into the afternoon. Police stated that they are focusing their investigation on the point where the fire is believed to have started.

They added that there is a possibility that additional inspections will take place tomorrow morning.

The Daejeon Metropolitan Police Agency has formed a dedicated 20-member investigation team led by Kim Yong-il, the Chief of the Detective Division (Senior Superintendent).

On the 28th, lithium-ion batteries burned in the fire at the National Information Resources Service in Yuseong-gu, Daejeon, are submerged in a fire-extinguishing water tank. On the 26th, a fire involving lithium-ion batteries for an Uninterruptible Power Supply (UPS) broke out at the NIRS, which houses government computer systems, causing a large-scale disruption to government digital services. Yonhap News.

The dedicated investigation team is focusing its efforts on determining the cause of the explosion of the lithium-ion batteries used for the Uninterruptible Power Supply (UPS).

They plan to question managers and other personnel to determine if there were any issues with battery management or if safety measures were inadequate.

As of now, the Ministry of the Interior and Safety and the NIRS explain that the incident occurred while 13 workers were moving UPS batteries—which were kept with servers in the 5th-floor server room of the NIRS—to the basement, when a fire broke out from one of the batteries that had been disconnected.

While some observe that the fire may have been caused by aging batteries, suspicions have also been raised regarding potential operator error during the relocation process.

According to the Ministry of the Interior and Safety, the UPS batteries involved in the fire were supplied to and installed at the NIRS in August 2014. They had exceeded their recommended 10-year service life by approximately one year.

In response, the Ministry stated, "We have been receiving regular inspections from the maintenance company that supplies the batteries, and no issues were identified during those inspections."

Some in the industry argue that the process requires cutting off the power before disconnecting the wires, and suggest that an electrical short may have occurred because the wires were disconnected without first cutting off the power.

Some have also suggested that the management by KT, which is responsible for facility maintenance, should be scrutinized.

However, during a briefing at the site yesterday, the NIRS explained, "Sparks occurred 40 minutes after the power was cut."

A police official stated, "As the restoration of government services is the top priority, we will determine the circumstances and cause of the fire through detailed inspections while monitoring the progress of the service restoration."

On the 28th, an official from the National Forensic Service examines batteries submerged in a fire-extinguishing tank at the site of the fire at the National Information Resources Service in Yuseong-gu, Daejeon. On the 26th, a fire involving lithium-ion batteries for an Uninterruptible Power Supply (UPS) broke out at the NIRS, which houses government computer systems, causing a large-scale disruption to government digital services. Yonhap News.

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