The film, which released on the streaming platform Disney+ last week, met with widespread outrage after it extended "special thanks" to top government bodies such as the Chinese Communist Party's (CCP) Publicity Department, as well as the Public Security Bureau and Tourism Department of Turpan - a city near Xinjiang with a large Uighur population.
"Disney should disclose the details about when #Mulan was filmed in Xinjiang, what assistances it received from authorities, what agreements it had made with them in order to do the filming, and what kind of human rights due diligence it conducted before making the decisions", Human Rights Watch China researcher Yaqiu Wang said on Twitter.
But rights groups and foreign media have reported that official documents and satellite images show the facilities are equipped and run like prisons.
At the time of the message, many called for an early boycott of the movie. The Bureau of Public Security has been specifically targeted by the US Government for its violation of human rights in the region. Some have been subjected to forced sterilization and abortion, and in recent months, ordered to drink traditional Chinese medicines to combat the coronavirus outbreak.
Is China detaining Uighur Muslims in secret camps? "The establishment of vocational skills education and training centers in Xinjiang in accordance with the law is a useful attempt and active exploration for preventive counter-terrorism and de-radicalization".
Part of the film was also shot in New Zealand, home of the director, Niki Caro. Disney has not commented on Mulan's production connections to Xinjiang.
But the film - which is based on a traditional Chinese legend about a female warrior who disguised herself as a man and took her father's place in the army - has already faced controversy and setbacks.
It has led to renewed calls for a boycott of the film, which also came under fire a year ago when Chinese actress Liu Yifei, who plays Mulan, voiced support for Hong Kong's police force during pro-democracy protests. Hong Kong pro-democracy advocate Joshua Wong tweeted.
"Mulan" is crucial to Disney's recovery after the pandemic forced cinemas around the world to close or operate under tight restrictions this year, prompting delays of the originally planned March debut.
That release was delayed after Disney's relations with China soured over "Kundun", its 1997 movie based on the life of the exiled Dalai Lama, whom China has branded a unsafe separatist.
However, the film's explicit credits to Xinjiang authorities have reignited the boycott movement.
"I support the Hong Kong police".