BEIJING (AP) — When it comes to ensuring the security of their regime, China’s Communist Party rulers don’t skimp.

The extent of that lavish spending was put on display when the boldest street protests in decades broke out in Beijing and other cities, driven by anger over rigid and seemingly unending restrictions to combat COVID-19.

The government has been preparing for such challenges for decades, installing the machinery needed to quash large-scale upheavals.

After an initially muted response, with security personnel using pepper spray and tear gas, police and paramilitary troops flooded city streets with jeeps, vans and armored cars in a massive show of force.

The officers fanned out, checking IDs and searching cellphones for photos, messages or banned apps that might show involvement in or even just sympathy for the protests.

An unknown number of people were detained and it’s unclear if any will face charges. Most protesters focused their anger on the “zero-COVID” policy that seeks to eradicate the virus through sweeping lockdowns, travel restrictions and relentless testing. But some called for the party and its leader Xi Jinping to step down, speech the party considers subversive and punishable by years in prison.

While much smaller in scale, the protests were the most significant since the 1989 student-led pro-democracy movement centered on Beijing’s Tiananmen Square that the regime still views as its greatest existential crisis. With leaders and protesters at an impasse, the People’s Liberation Army crushed the demonstrations with tanks and troops, killing hundreds, possibly thousands.

After the Tiananmen crackdown, the party invested in the means to deal with unrest without resorting immediately to using deadly force.

During a wave of dissent by unemployed workers in the late 1990s and early 2000s, the authorities tested that approach, focusing on preventing organizers in different cities from linking up and arresting the leaders while letting rank-and-file protesters go largely untouched.

At times, they’ve been caught by surprise. In 1999, members of the Falun Gong meditation sect, whose membership came to rival the party’s in size, surrounded the leadership compound in Beijing in a show of defiance that then-leader Jiang Zemin took as a personal affront.

A harsh crackdown followed. Leaders were given heavy prison sentences and members were subject to harassment and sometimes sent to re-education centers.

The government responded with overwhelming force in 2008, when anti-government riots broke out in Tibet’s capital Lhasa and unrest swept through Tibetan regions in western China, authorities responded with overwhelming force.

The next year, a police crackdown on protests by members of the Uyghur Muslim minority in the capital of the northwestern Xinjiang region, Urumqi, led to bloody clashes in which at least 197 were killed, mostly Han Chinese civilians.

In both cases, forces fired into crowds, searched door-to-door and seized an unknown number of suspects who were either sentenced to heavy terms or simply not heard from again. Millions of people were interned in camps, placed under surveillance and forbidden from traveling.

China has been able to muster such resources thanks to a massive internal security budget that reportedly has tripled over the past decade, surpassing that for national defense. Xinjiang alone saw a ten-fold increase in domestic security spending during the early 2000s, according to Western estimates.

The published figure for internal security exceeded the defense budget for the first time in 2010. By 2013, China stopped providing a breakdown. The U.S. think tank Jamestown Foundation estimated that internal security spending had already reached 113% of defense spending by 2016. Annual increases were about double those for national defense in percentage terms and both grew much faster than the economy.

There’s a less visible but equally intimidating, sprawling system in place to monitor online content for anti-government messages, unapproved news and images. Government censors work furiously to erase such items, while propaganda teams flood the net with pro-party messages.

Behind the repression is a legal system tailor-made to serve the one-party state. China is a nation ruled by law rather than governed by the rule of law. Laws are sufficiently malleable to put anyone targeted by the authorities behind bars on any number of vague charges.

Those range from simply “spreading rumors online,” tracked through postings on social media, to the all-encompassing “picking quarrels and provoking trouble,” punishable by up to five years in prison.

Charges of “subverting state power” or “incitement to subvert state power” are often used, requiring little proof other than evidence the accused expressed a critical attitude toward the party-state. Those accused are usually denied the right to hire their own lawyers. Cases can take years to come to trial and almost always result in convictions.

In a further disincentive to rebel, people released from prison often face years of monitoring and harassment that can ruin careers and destroy families.

The massive spending and sprawling internal security network leaves China well prepared to crackdown on dissent. It also suggests “China’s internal situation is far less stable than the leadership would like the world to believe,” China politics expert Dean Cheng of the Heritage Foundation wrote on the Washington, D.C.-based conservative think tank’s website.

It’s unclear how sustainable it is, he said. “This could have the effect of either changing Chinese priorities or creating greater tensions among them.”

HONG KONG (AP) — Videos of hundreds protesting in Shanghai started to appear on WeChat Saturday night. Showing chants about removing COVID-19 restrictions and demanding freedom, they would only stay up for only minutes before being censored.

Elliot Wang, a 26-year-old in Beijing, was amazed.

“I started refreshing constantly, and saving videos, and taking screenshots of what I could before it got censored,” said Wang, who only agreed to be quoted using his English name, in fear of government retaliation, . “A lot of my friends were sharing the videos of the protests in Shanghai. I shared them too, but they would get taken down quickly.”

That Wang was able to glimpse the extraordinary outpouring of grievances highlights the cat-and-mouse game that goes on between millions of Chinese internet users and the country’s gargantuan censorship machine.

Chinese authorities maintain a tight grip on the country’s internet via a complex, multi-layered censorship operation that blocks access to almost all foreign news and social media, and blocks topics and keywords considered politically sensitive or detrimental to the Chinese Communist Party’s rule. Videos of or calls to protest are usually deleted immediately.

But images of protests began to spread on WeChat, a ubiquitous Chinese social networking platform used by over 1 billion, in the wake of a deadly fire in the western city of Urumqi Friday. Many suspected that lockdown measures prevented residents from escaping the flames, something the government denies.

The sheer number of unhappy Chinese users who took to the Chinese internet to express their frustration, together with the methods they used to evade censors led to a brief period of time where government censors were overwhelmed, according to Han Rongbin, an associate professor at the University of Georgia’s Public and International Affairs department.

“It takes censors some time to study what is happening and to add that to their portfolio in terms of censorship, so it’s a learning process for the government on how to conduct censorship effectively,” said Han.

In 2020, the death from COVID-19 of Li Wenliang, a doctor who was arrested for spreading rumors following an attempt to alert others about a “SARS-like” virus, sparked widespread outrage and an outpouring of anger against the Chinese censorship system. Users posted criticism for hours before censors moved to delete posts.

As censors took down posts related to the fire, Chinese internet users often used humor and metaphor to spread critical messages.

“Chinese netizens have always been very creative because every idea used successfully once will be discovered by censors the next time,” said Liu Lipeng, a censor-turned-critic of China’s censorship practices.

Chinese users started posting images of blank sheets of white paper, said Liu, in a silent reminder of words they weren’t allowed to post.

Others posted sarcastic messages like “Good good good sure sure sure right right right yes yes yes,” or used Chinese homonyms to evoke calls for President Xi Jinping to resign, such as “shrimp moss,” which sounds like the words for “step down” as well as “banana peel”, which has the same initials as Chinese President Xi Jinping.

But within days, censors moved to contain images of white paper. They would have used a range of tools, said Chauncey Jung, a policy analyst who previously worked for several Chinese internet companies based in Beijing.

Most content censorship is not done by the state, Jung said, but outsourced to content moderation operations at private social media platforms, who use a mix of human and AI. Some censored posts are not deleted, but may be made visible only to the author, or removed from search results. In some cases, posts with sensitive key phrases may be published after review.

A search on Weibo Thursday for the term “white paper” turned up mostly posts that were critical of the protests, with no images of a single sheet of blank paper, or of people holding white paper at protests.

It’s possible to access the global internet from China by using technologies such as virtual private networks that disguise internet traffic, but these systems are illegal and many Chinese internet users access only the domestic internet. Wang does not use a VPN.

“I think I can say for all the mainlanders in my generation that we are really excited,” said Wang. “But we’re also really disappointed because we can’t do anything… They just keep censoring, keep deleting, and even releasing fake accounts to praise the cops.”

But the system works well enough to stop many users from ever seeing them. When protests broke out across China over the weekend, Carmen Ou, who lives in Beijing, initially didn’t notice.

Ou learned of the protests only later, after using a VPN service to access Instagram.

“I tried looking at my feed on WeChat, but there was no mention of any protests,” she said. “If not for a VPN and access to Instagram, I might not have found out that such a monumental event had taken place.”

Han, the international affairs professor, said that censorship “doesn’t have to be perfect to be effective”

“Censorship might be functioning to prevent a big enough size of the population from accessing the critical information to be mobilized,” he said.

China’s opaque approach to tamping down the spread of online dissent also makes it difficult to distinguish government campaigns from ordinary spam.

Searching Twitter using the Chinese words for Shanghai or other Chinese cities reveals protest videos, but also also a near-constant flood of new posts showing racy photos of young women. Some researchers proposed that a state-backed campaign could be seeking to drown out news of the protests with “not safe for work” content.

A preliminary analysis by the Stanford Internet Observatory found lots of spam but no “compelling evidence” that it was specifically intended to suppress information or dissent, said Stanford data architect David Thiel.

“I’d be skeptical of anyone claiming clear evidence of government attribution,” Thiel said in an email.

Twitter searches for more specific protest-related terms, such as “Urumqi Middle Road, Shanghai,” produced mainly posts related to the protests.

Israeli data analysis firm Cyabra and another research group that shared analysis with the AP said it was hard to distinguish between a deliberate attempt to drown out protest information sought by the Chinese diaspora and a run-of-the-mill commercial spam campaign.

Twitter didn’t respond to a request for comment. It hasn’t answered media inquiries since billionaire Elon Musk took over the platform in late October and cut back much of its workforce, including many of those tasked with moderating spam and other content. Musk often tweets about how he’s enacting or enforcing new Twitter content rules but hasn’t commented on the recent protests in China.

___

Story: Zen Soo. AP Business Writer Kelvin Chan in London and AP Technology Writer Matt O’Brien in Providence, Rhode Island contributed to this story.