HONG KONG, July 6 (Reuters) - Macau has locked down one of the city's most famous hotels, the Grand Lisboa, after more than a dozen COVID-19 cases were found there on Tuesday, with infections spreading rapidly in the world's biggest gambling hub.

At least 16 other buildings across the special Chinese administrative region are also locked down with no one allowed to exit or enter.

The authorities have placed more than 13,000 people under quarantine orders as the city battles to contain its biggest outbreak since the pandemic began. Macau has recorded more than 900 coronavirus infections since mid-June, prior to that it had largely been COVID-free since an outbreak in October 2021.

The Grand Lisboa is the second casino hotel locked down in recent weeks. Owned by SJM Holdings, which was started by former Macau kingpin Stanley Ho, the Lisboa is one of the city's most well known landmarks.

Local media showed photos of the hotel sealed off with people in protection gear and hazmat suits standing outside. The Grand Lisboa was not immediately available for comment.

While the government has stopped short of imposing a full scale lockdown in the former Portuguese colony, seen in Chinese cities such as Shanghai, most facilities are shut and restaurants can only provide takeaway.

Residents have been asked to stay at home as much as possible and are required to take part in three citywide COVID-19 tests this week. People are also required to take rapid antigen tests in between.

Only Macau's casinos have been allowed to stay open in a move to ensure job security. The government relies on the industry for more than 80% of its tax revenue with most of the population employed directly or indirectly by the casino resorts.

While casinos are physically open, there are few patrons inside and only a small number of staff, with many employees asked to stay at home to comply with the government's request.

Macau adheres to China's "zero-COVID" policy which aims to eradicate all outbreaks, at just about any cost, running counter to a global trend of trying to co-exist with the virus.

It still has an open border with mainland China, with its economy firmly hinged to the inflow of Chinese visitors. (Reporting by Farah Master; Editing by Jacqueline Wong)