(Bloomberg) -- South Koreans in Seoul woke up Wednesday to air raid sirens and warnings on their mobile phones to immediately evacuate — only to be told 20 minutes later that it was all a mistake. 

Residents in the country’s biggest city received a mobile push alert at 6:41 a.m. telling them to seek shelter about 10 minutes after North Korea launched a rocket carrying a military space satellite. Rare air raid sirens blared across the city and instructions to take cover filtered through loudspeakers on the streets.

Morning commuters rushed back toward subway stations, which are designed to be used as shelters in South Korea. Cars pulled back into garages to take cover. People called and messaged loved ones. 

But about 20 minutes after the initial alert, residents got a message from the federal Ministry of the Interior and Safety telling them the initial warning was sent in error. Seoul itself didn’t lift their alert until 7:25 a.m.— nearly a full hour after the first one was sent. 

Lee Woosoon, 46, was just opening his bakery in the business district of Euljiro when he got the first alert. 

“I immediately thought of my wife and daughter,” Lee said. “Even if I wanted to evacuate, I didn’t know where to go or what to do.” 

Safe Enough

He called his wife, who wasn’t picking up her phone, but after looking at a few headlines online, figured it was safe enough to continue working. After the government said the message was a mistake, he found himself laughing off the entire incident with customers.  

“It was a lot of confusion for nothing,” he said.

South Koreans, who are by now accustomed to their northern neighbor’s frequent missile launches, panicked this time because there were no details in the first alert and it’s rare for the government to issue a warning. Adding to the confusion was a brief outage of Naver, South Korea’s largest search engine, as millions turned to the app for information.

Naver’s mobile webpage and app service were disrupted for about 5 minutes due to soaring traffic, a spokesperson said in a text message, and it was immediately restored.

The panic quickly subsided into everyday reality for South Koreans. Chung Yuyoung, a web designer for a major Korean firm, was awakened by the alert on her phone.

“I thought I would die if I don’t act immediately,” the 34-year-old said. “It was not knowing what it was — whether it was a nuclear test, an earthquake or a war or a typhoon — that increased the fear.”

She would start her shift at home — just an hour later than usual. 

Seoul Mayor Oh Se-Hoon apologized for confusing citizens, but defended the city’s actions. 

“This emergency text message may have been an overreaction by field officials, but I believe it was not an error,” Oh said in press briefing Wednesday, adding that the city is investigating the matter. 

Disrupting Sleep

The Kospi opened higher on Wednesday morning to rise above the bull market level as traders brushed off the fiasco. The stock benchmark later erased gains amid broad weakness in Asian equity markets.

Seo Sang-Young, a strategist at Mirae Asset Securities, said he heard an announcement outside of his office downtown asking people to take shelter.

“If this type of alert was issued while the market was trading, the market could have seen a sharp and sudden drop because it could scare ordinary people,” he said — adding that it would present a good buying opportunity if that happened. “This type of event affects psychology but it doesn’t affect companies’ fundamentals.” 

Others in the business district shrugged off the alarms entirely. 

“My first thought was: ‘It’s disrupting my sleep time,’” said Eung Joo Lee, a currency trader at Daegu Bank. “People are becoming desensitized to North Korean missiles. In fact, North Korea has already warned us. I don’t think it will affect prices.” 

--With assistance from Youkyung Lee, Daedo Kim and Sohee Kim.

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