Police have cracked down on an illegal gambling house disguised as a regular business office in Gangnam, southern Seoul, which reportedly wagered hundreds of billions of won in bets.

Seoul Metropolitan Police’s International Crime Investigation Unit said Thursday that it has apprehended the 54-year-old ringleader, who allegedly ran gambling establishments across the Nonhyeon, Sinsa and Yeoksam neighborhoods from June 2023 to August 2024. The man has been charged with violating the Tourism Promotion Act and has been transferred to the prosecution for possible indictment.

In addition, 20 dealers and staff members that worked at the gambling house were detained on charges of aiding gambling. Thirteen people could also face charges for participating in gambling.

Authorities estimate the gambling operation handled around 65 billion won ($46.5 million) over a 14-month period. Police confiscated 205 million won in illegal profits from the ringleader during the raid.

The investigators said an ordinary office space was converted into a casino, filled with gambling tables, monitors and a lounge area.

It was run as an online broadcast gambling house that streams gambling scenes from a Philippine hotel-casino in real time on a monitor, allowing participants to place bets while watching.

The clients were mostly in their 40s and 50s and were said to have placed bets of up to 400 million won.

Professional dealers who had worked in casinos were in charge of the betting chips, while other staff members provided food and drinks to customers, to give a more authentic casino vibe.

To avoid detection, the ringleader rented office space on a short-term lease and moved three times over 14 months. The organization also installed surveillance cameras around the building and operated on a membership basis, only accepting clients upon referral.

After receiving a tip that illegal gambling was taking place at an office building in Gangnam, police staked out the location in August and were able to catch it in action, timing the raid with a delivery food driver entering the building.