On 10 January, the day the Southern Weekly published a new edition after staff ended strike action in protest at censorship, Yi Nengjing posted on microblogging site Sina Weibo: "I have to go to tea now. Hope it's good."
The six million followers of the Taiwanese artist, who has a large fan base in mainland China, immediately had an inkling she may be in trouble.
Soon afterwards, she went silent on Weibo and her previous posts supporting the Southern Weekly disappeared.
But many had already been reposted, including the one in which she mocked the Global Times newspaper as "dogs", and the one in which she wrote: "Your rage makes me realise that I am right; your cover-up makes me believe I am just; your madness makes me sober, and your killing makes me aware that I am alive."
Yi Nengjing was not the only high-profile figure to have received an "invitation for tea". Former deputy CEO of Google Li Kaifu posted on 7 January that "the tea was really bitter", adding: "From now on, I can only talk about East, West and North; and Monday to Friday only."
In other words, he was not able to talk about South, and weekend, a reference to the newspaper at the centre of the censorship row.
Similarly, real estate guru Ren Zhiqiang posted on Sina Weibo: "Got a call after midnight, an invitation to tea."
Prior to being invited to tea, all three had posted comments in support of the staff at the Southern Weekly as events unfolded.
In the Chinese political language, "to be invited for tea" has become a euphemism for being questioned by the police.
The invitation comes from the authorities in the form of a phone call, and a knock on the door.
Those being invited range from celebrities who have expressed strong views on a topical issue to well-known dissidents and young people who get bold on the internet.
The questioning normally lasts a few hours - tea might or might not be drunk during the session. The security people will ask you about your activities and issue warnings to stop or face the consequences.
Degrees of harassment
So since when has the centuries-old tradition of tea-drinking taken on such sinister overtones?
Nobody can tell exactly. After the Tiananmen crackdown in 1989, some intellectuals received such invitations.
But the practice became better known as internet use spread and people talked about their experiences openly on social media sites.
In a book published in 2012 entitled Encounters with the Police, co-authors Hua Ze, a journalist and documentary-maker, and Prof Xu Youyu, a well-known political scholar, compiled testimonies of 21 people, among them human rights activists and "netizens". All of them have been "invited to tea" and subjected to other forms of police harassment. The measures they mentioned include:
- Home surveillance: where security people stay outside a person's home and follow them if they go out
- House arrest: where a person is confined to their home, where they might or might not be able to go online and contact friends
- Kidnapping: the most serious form of intimation, where unidentified people use force to take a dissident to a place where they are questioned, tortured, and seriously threatened.
Both authors have experienced some forms of such harassment. Hua Ze was "invited for tea" after publishing some articles online in 2010 touching on political issues.
Seven policemen showed up at her home and asked her to follow them. They drove to a nearby police station.
The conversation was quite polite, she recalls. They asked her if the articles had been written by her, with whom she had been in touch, and if anybody had asked her to write the words.
Hua Ze felt that the police were not interested in verifying that she had written the articles, but instead they wanted to find out how they came about, and if she was involved with organising anything.
After this experience, Hua Ze understood that she was being watched all the time, her phone was tapped, and her computer and activities placed under surveillance. She says there are others who become paranoid after such an experience.
Hua Ze is convinced that this is exactly what the authorities want to achieve - to instil fear in people so that they give up activism themselves.
Apart from "tea drinking", dissidents are also known to have been "invited" to take holidays outside Beijing before important anniversaries, conferences or state visits, all at the expense of the state, which, according to reports, has a budget of over 700bn yuan (around £70bn, $110bn) in 2012 to "maintain stability and harmony".