[2] As in previous years, Chinese authorities launched an extensive "stability maintenance" campaign in which activists and others likely to criticise the government are transported to locations outside of Beijing or placed under house arrest; social media is scrubbed of terms and images referring to the protests.

[3] Due to the severe censorship, most of the younger generation in China, such as Chinese university students, are totally ignorant of the protests in 1989 and the government crackdown on 4 June 1989.

Speaker of the United States House of Representatives, Nancy Pelosi, caricatured this by saying that young Chinese thought that 'Tank Man' was the star of a soft drink advertisement.

[4] Two censors at Beijing ByteDance Co Ltd, a Chinese internet company that performs online censorship, say China now possesses tools to automatically detect and block content related to the event, and can now identify posts containing sensitive terms with unprecedented levels of accuracy, aided by machine learning and voice and image recognition.

Searches of terms related to the Tiananmen crackdown, along with other sensitive issues including Taiwan and Tibet, are now largely automated owing to artificial intelligence.

[8] The British embassy in Beijing, which put out a statement from foreign secretary, Jeremy Hunt, on its Weibo channel to commemorate the anniversary reported that the post had been deleted from domestic social networks.

Accounts that were blocked included those belonging to dissident writers and an activist who has helped document the disappearance of Uighurs in China's restive Xinjiang region.

Twitter said that the firm had been caught up in an ongoing effort to clear up accounts "engaging in various forms of platform manipulation, including spam and other inauthentic" behaviour, and that errors may have been made or that such routine actions thrown up false positives.

Having been placed under house arrest since 17 January, the 14th anniversary of the death of the reformist leader Zhao Ziyang, who opposed sending tanks into Beijing, she is likely to be taken many miles away from the capital until after 4 June.

[1] Tiananmen Mother Zhang Xianling, whose son was killed during the army suppression, reported the presence of state security officers outside her house on the anniversary of Zhao's death and also paid her a visit on 4 May.

[13] In late May, Ding Zilin, founder of the group, was taken from her Beijing home by state security and sent to her native Jiangsu province, where she would spend the anniversary out of the potential spotlight.

Although the product was seized, one bottle that survived was smuggled out of the country made a symbolic trip around the world, to the Middle East, France, the US and eventually Hong Kong, where it was put on display in the June 4th Museum.

[15][16] Chinese rock musician Li Zhi [zh], who had sung ballads about social ills and who had been outspoken about the Tiananmen Square protests, reportedly disappeared from public view three months prior to the anniversary.

[17] Feng Congde (Chinese: 封從德), dissident and a student leader of the protests, who may have flown in to attend the anniversary candlelight vigil in Victoria Park, has reportedly disappeared after arriving in Hong Kong on a flight from Tokyo.

[19] The Alliance condemned his removal from Hong Kong, alleging that the government had created a 'blacklist of dissidents', whilst the Immigration Department declined to comment on individual cases.

The artwork, which draws inspiration from the iconic photograph "Tank Man" by Jeff Widener that he took from his Beijing hotel room on the fateful day, was installed outside the Chiang Kai-shek Memorial Hall two weeks before the 30th anniversary.

[26] China Labour Solidarity called for a Tiananmen anniversary picketing in front of the Chinese Embassy at 49 Portland Place, London on Saturday 1 June at 1 pm.

[29] According to Hong Kong Watch, The Green Party faction in the Bundestag is hosting a seminar entitled "30 years after the Tiananmen massacre: Responding to a changing China" to mark the anniversary.