The Marriott International hotel chain has apologised and condemned "separatists" in China after the Beijing government shut down its website over an online questionnaire that suggested some Chinese regions were separate countries.
Delta Air Lines Inc., the Zara apparel chain and Irish medical-equipment maker Medtronic Plc all came under fire.
The Chinese government frequently erupts with outrage at any perceived contradiction to its territorial claims, claiming such statements upset all of China's 1.4 billion citizens. The companies were asked to change the "illegal" contents.
The airline has been instructed to "immediately rectify the situation" and "publicly apologise", CAAC said.
The Marriott website has since been shut down.
"Meanwhile, they should respect China's sovereignty and territorial integrity, abide by Chinese law, and respect the Chinese peoples' feelings, which are the foundation for any corporation to do business in any country", spokesperson Lu Kang said at a daily press briefing.
"We never support any separatist organisation that damages China's sovereignty and territorial integrity", it says.More news: Hazard Set To Sign Chelsea Contract Extension Amid Madrid Interest
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Marriott sent out a mail questionnaire to its Chinese members Tuesday morning, which listed Tibet, Hong Kong, Macao and Taiwan as options under the question "Which country are you from?"
"We will learn from this experience, make changes to ensure errors like this don't happen again, and continue to focus on making sure our Chinese guests feel respected and have wonderful experiences as we have the privilege of serving them in our hotels in China and around the globe".
The Tibet Autonomous Region (TAR) is one of two autonomous provinces in China, while Hong Kong and Macau are designated as special administrative regions.
Shanghai officials issued a notice late Wednesday, saying that they had launched a probe into whether Marriott International's Mandarin-language questionnaire violated laws on adverting or national cybersecurity.
It said others in the industry should heed this as a warning.
Marriott is also investigating the "careless like" by one of its official social media accounts of a pro-Tibet tweet that suggested its support for the position.
China and Taiwan - officially the People's Republic of China and the Republic of China - separated in 1949 following the Communist victory on the mainland after a civil war.
The company's President and CEO Arne Sorenson described the Twitter gaffe as "misconduct by an individual member of staff".