"Has Mass Surveillance Begun?": The Truth Behind Hongik University Station CCTV [Fact Check]

Recently, a conspiracy theory surrounding the CCTV at Hongik University Station on the AREX (Airport Railroad Express) line spread on social media. It started late last month when a social media user posted a photo of an escalator CCTV at AREX Hongik University Station.

The photo appears to show a real-time CCTV monitor at a station escalator, with green boxes and numbers displayed over every passenger. The user raised concerns along with the sentence "Has mass surveillance begun?", suggesting that a nationwide surveillance infrastructure was being introduced.


The post spread rapidly, reaching nearly 200,000 views. Heated comments followed, such as "It has finally come to this," "Are we just supposed to sit back helplessly?", and "There is no other way than to overthrow it."

The SBS Fact Check team investigated what was actually happening.


First, the author of the post claimed that this was a case similar to China.

Indeed, China is known to have begun developing a criminal tracking system using CCTV, dubbed 'Skynet' (Tianwang), since 2004. There were also domestic media reports in China. China's state broadcaster CCTV reported on the system in detail nine years ago. The report stated that China was building a system with over 20 million intelligent CCTVs nationwide, capable of identifying specific individuals not only through facial recognition but also through features like clothing and gait.

 
Naturally, concerns arose. There were multiple reports that facial recognition technology was being used to monitor dissidents.

The National Endowment for Democracy (NED) in the United States published a report in February 2025, stating that such nationwide surveillance networks would shrink democracy.


So what is the situation with the CCTV at Hongik University Station on the AREX line?

Upon investigating the Hongik University Station CCTV, it was true that, as spread on social media, green boxes and numbers appear when people are detected near escalators.

The SBS Fact Check team sent a written query directly to Airport Railroad Corp. (AREX) asking about its purpose. AREX replied as follows:
 
Due to the nature of the Airport Railroad, which serves many airport passengers, safety accidents involving luggage on escalators are frequent. AREX explained that when AI detects that a passenger is not holding their luggage handle, the system displays a warning screen to prompt the passenger to hold the handle again. The goal is to improve the warning system into a 'responsive' one that alerts only during risky situations, as continuous public announcements can increase fatigue and make passengers desensitized to warnings.

They added that the green rectangles and numbers appearing over individuals are merely temporary identifiers assigned by the AI to distinguish and track people's movements in the video, and faces are processed to ensure they cannot be identified.


In fact, AREX has publicly announced its AI CCTV accident prevention system multiple times. For instance, in November last year, it issued a press release announcing the signing of a business agreement with the Korea Transportation Safety Authority for intelligent AI CCTV technology development, which received extensive media coverage.

In June, at the "Symposium on Strengthening Cooperation Among Related Agencies for Railway Safety Management System" hosted by the Korea Transportation Safety Authority, AREX presented material titled <Establishment of Object Recognition Intelligent AI CCTV System at Hongik University Station>, which contained the same details.


Looking at the symposium materials, faces were processed so that identification was impossible, and the real-time CCTV photos circulating on social media showed the exact same thing. It can be seen that passengers' faces are covered in yellow.


AREX further stated in response to SBS's inquiry: "The AI CCTV being pilot-tested at Hongik University Station has no facial recognition or personal identity verification function. Furthermore, the AI CCTV installed at Hongik University Station operates solely on an independent internal network physically separated from the external internet, so data is not transmitted externally, and videos are not recorded."

According to data from the Ministry of the Interior and Safety, around 650,000 CCTVs are installed across integrated control centers in 217 local governments nationwide, monitoring every corner 24 hours a day. AI technology is applied to approximately 37.5% of these, but it is explained that this is not used to identify specific individuals or track their movements. Instead, the purpose is to prevent disasters by quickly detecting signs of danger, such as urban flooding or wildfires.


In the AI era, growing concerns over surveillance and personal data leaks are natural. People are hesitant even to scan a single QR code, and many voice suspicions over whether AI might be surveilling individuals without our knowledge. A civic attitude of constantly monitoring power and technology and raising questions can be a healthy stance.

However, such suspicions must naturally be grounded in reasonable evidence. If unfounded speculations spread as conspiracy theories, they will excessively heighten societal distrust, ultimately leading to outcomes that harm the health of democracy. What is needed most in the AI era is neither blind faith nor unconditional fear of technology, but rather healthy doubt based on facts.

The claim that "Hongik University Station on the Airport Railroad has CCTVs surveilling citizens like in China" is rated as "NOT TRUE" by the SBS Fact Check team.

 
(Writer: Kim Hyo-jin, Intern: Park Geun-ho)
※ Please note: This article was translated by AI and may contain errors.