Dong Yaoqiong earlier this month posted a video of herself protesting Xi Jinping and the Chinese Communist Party, pouring ink on a poster of the Chinese president.

The video has been taken down, and nobody has seen her.

Her father and a Chinese artist supporting her were detained and have also gone missing after publicly demanding her whereabouts, two news outlets reported.

China has been trying to cement Xi's position as the most powerful person in the country.

A Chinese woman has been missing for two weeks after posting a video of herself pouring black ink over a poster of President Xi Jinping.

Dong Yaoqiong posted the video of her protest on July 4 and hasn't been seen since. The original video was removed from her Twitter account, @feefeefly, but has been reposted by supporters.

In the video — in which she identifies the time as shortly after 6:40 a.m. and her location as Shanghai's Lujiazui financial district — Dong can be heard repeatedly shouting "I am against Xi Jinping and the Chinese Communist Party" and accusing the party of carrying out "oppressive brain control."

After defacing a poster of Xi's face, Dong says: "Seen it yet? This was my behavior." She can then be seen waving to commuters passing by.

A version of the video was reposted by the Chinese artist Hua Yong, though some of the audio and visuals don't match up entirely:

Later that afternoon, Dong posted photos of what appear to be police officers from a door's peephole.

According to the Hong Kong Free Press, she said: "Right now there are a group of people wearing uniforms outside my door. I'll go out after I change my clothes. I did not commit a crime. The people and groups that hurt me are the ones who are guilty."

She has not been seen since that broadcast, and those photos have disappeared from her Twitter account.

A member of China's People's Liberation Army guarding a billboard of Xi in Hong Kong. Anthony Kwan/Getty

Hua and Dong's father, Dong Jianbiao, have been detained while publicly demanding to know her whereabouts, Agence France-Presse and Radio Free Asia reported.

Hua and Dong Jianbiao livestreamed a video on Friday in which Dong identified himself and called for his daughter's release. A man purporting to be a plainclothes police officer then knocks on the door and can be heard saying he wants to take the pair away for investigation.

The video ends with the man entering the property and ignoring Hua's question about whether he has a search warrant.

Hua was detained for questioning and released on Monday but has not been seen in person, a friend of his told Radio Free Asia. The friend added that Dong Jianbiao had most likely been escorted back to his hometown.

BEIJING, CHINA - MARCH 20: China's President Xi Jinping, center, drinks tea during the closing session of the National People's Congress at The Great Hall Of The People on March 20, 2018 in Beijing, China. The annual gathering of Chinese lawmakers concluded with a nationalistic speech by president Xi Jinping, his first public address since the abolishment of term limits marked the beginning of his indefinite rule. Xi spoke confidently of China's determination to take its place in the world, and gave the strongest sign in decades that the Communist government wants to bring Taiwan back under Beijing's control. Xi warned that China would never allow 'one inch' of territory to be separated from it, and said any attempts to split China will receive 'the punishment of history'. The denunciation appeared to be aimed at the United States, after U.S. President Donald Trump signed the Taiwan Travel Act this week that allows high-level U.S. visits to Taiwan. Xi's speech earned wide applause from the nearly 3,000 loyal delegates at the National People's Congress, which voted earlier this month to amend the constitution to allow the 64-year old Xi the possibility of being a 'leader for life'. The concentration of virtually unchecked power has stirred worries of China's return to an era of autocratic rule not seen since Mao Zedong. (Photo by Kevin Frayer/Getty Images) Kevin Frayer/Getty

Dong Yaoqiong's protest comes as China ramps up its efforts to secure Xi's position as the most powerful man in the country. China abolished presidential term limits earlier this year, meaning Xi can rule for life if he wants to.

People seen as a threat to China's ruling party have mysteriously gone missing in the past. In 2015, five Hong Kong booksellers that had sold works critical of Chinese leaders disappeared over two months. All have since reappeared, while four talked to state media appearing to confess to their alleged crimes against the Chinese state.

China has also routinely censored social-media posts appearing to criticize Xi.