While no human casualties have been reported, KT’s landline, mobile and internet networks in the area went down after the fire hit communications equipment that was installed in the basement of the building.

The network blackout affected mostly western Seoul including Mapo-gu, Seodaemun-gu, Yongsan-gu and Eunpyeong-gu and parts of Goyang in Gyeonggi Province. Services remained unavailable or spotty as of Sunday afternoon.

Seoul city sent emergency mobile phone alerts about the damaged network system on Saturday, but KT subscribers in the area were unable to receive the messages as phone services were down.

Police and fire stations in the affected areas were impacted as well because landline phone services were temporarily paralyzed on Saturday.

The Seodaemun, Yongsan and Mapo police stations, where the communications network system didn’t work properly on Saturday, sent their police officers to the Seoul Metropolitan Police Agency and listened for reports via radio messages.

Fire stations struggled to receive landline phone calls Saturday, but were able to respond to emergencies because their online command system was not affected by the fire.

Severance Hospital in Sinchon continued to have problems with landline phone service as of Sunday afternoon. Making or changing appointments by phone has not been possible since the KT building fire on Saturday.

KT gave assurance that medical institutions will get priority as it goes about restoring services, but exactly when the service will be normalized remains uncertain for now, a hospital official said Sunday afternoon.

Convenience stores, restaurants and cafes that use KT’s communication network for their credit card payment systems were also directly impacted by the network damage.

“Many customers left without buying anything as they didn’t have cash,” the owner of a bakery in Sinchon told The Korea Herald. 

The bakery has been accepting wire transfers from customers without cash, but many customers simply gave up on their purchases, seeing it as too much of a hassle. The owner said there was a 40 percent drop in sales over the weekend compared with typical weekends.

The payment systems in convenience stores were disrupted by the network blackout. Notices saying “We only accept cash. Card payment is not available now,” were seen on the doors of convenience stores in Seodaemun-gu on Sunday afternoon.

“I don’t usually bring cash with me, so I was frustrated when I saw the notices,” said Kim Kwang-hyun, who was at a convenience store to buy a pack of cigarettes. Unable to withdraw cash because automated teller machines in the area were also out of operation due to the damaged network, he went back home to see if he could scrape together enough change for the cigarettes.

The sudden blackout affected college students in western Seoul, especially in Sinchon, where several universities are clustered.

On Sunday afternoon, numerous college students in Mapo-gu and Seodaemun-gu could be seen wandering around cafes, searching for Wi-Fi connections. 

Oh Eun-young, a Yonsei University sophomore, had to rush to Yeouido on Saturday night to submit her midterm paper online on time, as she couldn’t upload her file in Sinchon.

“I couldn’t use a Wi-Fi hot spot as all of our family members use KT. The internet router at home didn’t work as it’s provided by KT as well. I panicked,” Oh told The Korea Herald.

Police, fire authorities, KT and the Korea Electric Power Corporation surveyed the KT site in Ahyeon-dong on Sunday to determine the cause of the fire. While the exact cause is still under investigation, the authorities will carry out a second site inspection on Monday at 10 a.m. with the National Forensic Service.

By Park Ju-young (jupark@heraldcorp.com)