A chlorine leak at a five-star hotel on South Korea's Jeju Island sickened approximately 50 people, triggering a police investigation and public anger over the resort's handling of the incident, Chosunbiz reports.

The leak sent guests and employees scrambling for treatment, with dozens reporting symptoms consistent with chlorine exposure. The chemical, widely used in hotel pool sanitation and water treatment systems, becomes hazardous when containment fails or when it is improperly stored and mixed.

Authorities have opened a formal probe into the incident. Investigators are expected to examine the hotel's chemical storage protocols, maintenance records for its water-treatment equipment, and whether staff followed safety procedures in the hours before the leak. The response will determine whether the case proceeds as a criminal negligence matter or is resolved through regulatory penalties.

The incident has also drawn sharp criticism from the public. Jeju is one of South Korea's premier leisure destinations, and its five-star properties command premium room rates from both domestic and international travelers. A chemical safety failure at that tier of the market carries outsized reputational cost — and raises questions about how rigorously luxury operators on the island audit the back-of-house systems that guests never see.

For hotel operators, the case is a reminder of the operational exposure embedded in routine water chemistry. Chlorine-based systems require disciplined storage segregation, ventilation, and staff training, and lapses in any of those areas can convert an ordinary maintenance cycle into a mass-casualty event with legal, regulatory, and brand consequences attached.

The investigation remains ongoing, and its findings will likely shape stricter chemical-handling scrutiny for Jeju's high-end hotel sector in the months ahead.