(Bloomberg) -- The Chinese resort island of Hainan has placed more cities, including the provincial capital, into lockdown as a Covid-19 outbreak spreads, stranding tens of thousands of tourists in one of the nation’s most popular holiday destinations. 

The province reported 504 cases on Sunday, taking the current outbreak to almost 1,500 since the first infection was detected a week ago. The provincial capital Haikou -- a major flight hub for the island -- and the beachside resort city have been placed into lockdown, while Wanning and Qionghai are under “static management,” a term commonly used when referring to lockdowns. 

Overall, China reported 807 cases for Sunday, up from 736 on Saturday and the most in two weeks. The flare up in cases, from less than 300 as recently as Wednesday, shows the difficulty of meeting China’s strict Covid-Zero policy in the face of more infectious omicron sub-variants. After taming outbreaks in megacities like Shanghai and Shenzhen, cases continue to pop up in other regions.  

Tibet recorded four infections Sunday, the first in 920 days. The remote, mountainous region had detected just one prior case since the pandemic started. 

As of Saturday, 25,000 tourists were stuck in hotels in Sanya, according to a briefing by the provincial government on Sunday. Arrangements have been made for more than 3,000 tourists at Sanya Phoenix International Airport to stay at nearby hotels. The stranded travelers will have to pay half the room bill this week.  

More than 81 million tourists visited the island in 2021 and tourism spending rose to 250 billion yuan ($37 billion), both figures rising about 26% year-on-year. 

The lockdowns coincide with Hainan’s peak travel season, dealing a blow to the province’s duty free retail industry -- the most important duty free shopping market in China. China Tourism Group Duty Free Corp. shares fell as much as 7.5% in early trading Monday, before paring losses to recently be down 3%. 

The tropical city’s outbreak has spread to 10 cities and counties in Hainan, and to at least four other provinces, including Hunan and Guizhou, with each on Sunday reporting one infection coming from Sanya.

Meantime, China has shortened the length of suspensions for inbound airline flights that carry passengers infected with Covid. The so-called circuit breaker for flights that bring in five people with Covid, or 4% of the total passenger load, has been cut to one week, the Civil Aviation Administration of China said.

Authorities have been adjusting restrictions to staunch some of the fallout for the world’s second-largest economy, while remaining committed to its core Covid Zero policy. As omicron sub-variants become ever-more infectious, Xi’s zero tolerance resolve is growing stronger -- leading many experts to warn the approach could continue well beyond 2022.  

Read more: China’s Covid Zero Could Last for Years Because It Works For Xi

In June, China cut in half the length of time inbound travelers must spend in quarantine to 10 days, making it easier for citizens to return and foreign companies to tend to business in the world’s second-largest economy after 2 1/2-years of isolation.

(Adds provincial, national case tally in second, third paragraphs.)

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