Princess Margaret Hospital in Hong Kong received a report of unidentified gas at around 9am on September 16, according to an announcement issued the same day on behalf of the Hospital Authority. The Hospital Authority said the affected areas were floors 12 to 14 in block G, which it described as the working area of the Pathology Department, where no patient services or treatment facilities are located.

The hospital arranged for working staff and visitors on the affected floors to leave immediately, and firefighters and police later arrived to handle the situation. The hospital said it would work with the Fire Services Department to investigate the source of the unidentified gas. Emergency service at the hospital was not affected.