Marriott International, the world's largest hotel company, has been told to shut down its Chinese website and mobile apps for one week while it removes any illegal content on its platforms.
On Thursday, the Shanghai Cyberspace Administration urged the company to minimise the negative effect of having listed Tibet along with Taiwan, Hong Kong and Macao as countries in a survey sent to Chinese members of its rewards programme.
The authority has summoned managers of the company's China office, which is based in Shanghai, to a meeting.
In a statement issued on Wednesday, the Huangpu district government said the behaviour of Marriott International violated China's Cybersecurity Law and Advertisement Law.
The China National Tourism Administration said on Thursday it had instructed the Shanghai authorities to launch an investigation.
It also ordered hotels to review their websites and apps to ensure the information on them does not violate Chinese law. The administration said tourist accommodation is a core factor of a country's tourism industry.
"The image of the hotel industry is closely related to the image of China's tourism industry as a whole," the administration said in a statement.
Marriott Rewards, the membership programme of the company, has put out four statements and apology letters since Tuesday on its Sina Weibo account.
It said Marriott International fully respects China's sovereignty and territorial integrity, and sincerely apologised for any behaviour that may have led to a misunderstanding of the company's stance.
The illegal listing was first revealed on Sina Weibo by a personal account verified as Zhong Ju Sao Di in the Ningxia Hui autonomous region on Tuesday morning.
In an interview with Shanghai news portal thepaper.cn, he said that as a Marriott Rewards member, he received a questionnaire from the group and was required to select his country before filling out the poll.
He said he was infuriated when he saw Tibet, Hong Kong and Taiwan had been singled out as countries and decided to post snapshots of the pages online.
On Thursday afternoon, he claimed in a new post to have cancelled all his reservations with Marriott International for upcoming trips.
The Maryland-based hotel group announced in 2016 that it would double its presence in China, where it today operates more than 300 properties and has another 340 in the pipeline.
In August, it formed a joint venture with China's e-commerce giant Alibaba in an attempt to better connect with the country's hundreds of millions of travellers.