Government censors are finding new ways to block banned keywords on social media platforms as netizens tried, and failed, to discuss constitutional changes planned by the ruling Chinese Communist Party on social media platforms this week.
The planned changes, which will almost certainly be approved by China's parliament, the National People's Congress (NPC) next week, will pave the way for President Xi Jinping to remain in office indefinitely, prompting a public outcry which has been swiftly extinguished by government censors online.
The U.S.-based China Digital Times (CDT) website, which monitors Chinese internet censorship, found dozens of keywords had been blocked from search engines and social media posts in the wake of Sunday's announcement, including a large number referring in some way to China's imperial past and the lifelong rule of its emperors.
Oblique references to imperial themes were also blocked, including "yellow gown," "proclaimed emperor," and the title of an animated film "The Emperor's Dream."
The word "shameless" also fell victim to blocking algorithms, as did a merger between Xi's name and that of late supreme leader Chairman Mao, to produce "Xi Zedong," CDT reported.
Until now, China's internet censors have relied on software that can block text, but a recent research report from the international monitoring organization SANS Internet Storm Center found that images posted to WeChat are now also being successfully scanned for forbidden words and images.
"China has certainly come up with a way to not only filter keywords for billions of messages each day, but also apply these lists to images by performing large-scale [optical character recognition] on vast amounts of images essentially in real time," internet security expert Johannes Ullrich wrote in a post to the group's main website.
"Chinese activists find it more and more difficult to evade these filters effectively and to communicate with each other using state-controlled media like WeChat, which are the only real communication options given that many other services that do not comply with Chinese filtering laws are blocked," Ullrich said.
Meanwhile, anyone with a critical opinion of the government is finding their access to social media platforms cut off by the authorities.
Veteran Hebei-based journalist Zhu Xinxin said he has been prevented from posting to the platform after he criticized the proposed changes to the constitution.
"I can't post ... I can send money, and see some posts, but I can't say anything," Zhu said. "They want to create the false impression that the general public support their constitutional amendment."
"They are silencing any opposing voices."
Many chat groups shut down
Zhu said "many accounts and groups" on social media platforms have been shut down since the announcement.
"They have shut down a large number of chat groups and a lot of personal accounts," Zhu told RFA. "There is a democracy activist here in Shijiazhuang, and his group chat was shut down, probably because he was calling on people to vote against the constitutional amendments, and he has been barred from holding an account for life."
A WeChat user in Beijing surnamed Ma said his account was also shut down after he opposed the constitutional amendments online.
"I didn't send out any rumors; they just shut me down because I said something the authorities don't want to hear," Ma said. "I oppose the amendment, and I said in a commentary sent out to my chat group that I disagree."
"I don't think that amounts to subverting the government; they authorities just want to limit the expression of dissenting opinions," he said.
Official warnings have also been sent out to WeChat users, according to a user in the southern province of Guangdong surnamed Fan.
"They are using WeChat to send out warnings to people not to spread rumors and conjecture, nor anything with 'malicious' content, on pain
of being barred for life," Fan said.
He said his account was deleted earlier this week.
"After my account was deleted, they deleted vast numbers of accounts all across the country ... in a coordinated operation," Fan said. "They've been detaining people in some places, or inviting them to 'drink tea' [with the police] and so on."
"I think they must have already had a list, and when something big happened, they just started deleting accounts at will."
A social media user in Shanghai surnamed Ma said she is also concerned about the constitutional amendments, but doesn't expect any opposition to be effective.
"They will do whatever they want to do, and if ordinary people oppose them, they won't succeed," she said. "There are several forms of blocking now: keyword blocking [and] they can also block individuals so that it's hard for them to post anything at all, regardless of what it is."
Reported by Gao Feng and Xi Wang for RFA's Mandarin Service, and by Wong Lok-to for the Cantonese Service. Translated and edited by Luisetta Mudie.