On Sunday afternoon, a friend of Australian-Chinese artist Guo Jian in Beijing received a text message from the 52-year-old saying he had been taken away by the authorities. A second message said the people who took him away — most likely China’s feared State Security Bureau — told him he would be detained for 15 days. He is now locked up, unable to see anybody, not even a lawyer.

Guo Jian is the first Australian citizen among scores of people who have been detained in Beijing over the past month or so by Xi Jinping’s increasingly paranoid and ruthless regime. The reason for the paranoia is that this evening, June 3, marks 25 years since the People’s Liberation Army began rolling its tanks into the centre of Beijing to crush political reformist demonstrations that had started a month earlier. There were protests in 80 cities across China.

During the evening and next day, PLA troops proceeded to murder at least 250 and possibly thousands of Chinese citizens in cold blood, including protesters and innocent bystanders. China may look different two and half decades later — it’s richer and pushier — but not much has really changed.

Although the events of liu si (6-4, as it is known) shocked people to the core, few would be surprised if the leadership took such actions today to quell mass dissent. Violent oppression happens quietly every day in modern China to the point where most of the country’s people have been cowed into submission. Guo Jian and his fellow artists, writers, human rights lawyers, civil society advocates, academics, people who promote religious freedom and other crusaders are the brave ones.

The Tiananmen Square massacre is an event the Chinese Communist Party has tried to scrub from history, and most people under 40 in China have little idea what happened. For every promise of economic reform by Xi, lauded by the West, comes a fresh way by the party to fuck over their own citizens — usually ignored by the West.

I first met Guo Jian at a dinner party at the residence of the Australian Ambassador in Beijing, Geoff Raby. We struck up one of those slightly wine-fuelled conversations and within hours had decided to keep the party going, hitting the town until the wee hours. It was a serendipitous, instant friendship with a man who makes such things easy. When I lived in Beijing from 2009 until last year, he was a regular at Australian expatriate gatherings: always smiling, always laughing, always funny. Far from being the temperamental artist type, he’s a natural with people and has a wicked sense of humour.

His “crime” is daring to have a political conscience; daring to question. In the past, he has been invited in for “cups of tea” — the Chinese euphemism for being given a warning against dissent — but he has never been taken away before.

“It’s fair to say that any goodwill Australia may have built with Beijing over the search for … MH370 collapsed like a house of sand at the weekend…”

Guo Jian joined the army at 17 and later joined protests in Tiananmen. He moved to Australia in 1992, where he became a citizen and stayed for 13 years. He has even picked up something of a Sydney twang.

Last weekend, he landed the coveted spot of guest/interviewee in the Financial Times Weekend Edition’s “Lunch with …” feature, and recently appeared on two separate programs on the ABC: an edition of Q&A filmed in Shanghai in April and, together with Raby (with whom he is close friends), in an episode of Two Men and a Tinny, talking about Chinese art.

It appears that his revelation in the Financial Times story that he had created a sculpture of Tiananmen Square covered with litter and minced pork to commemorate the anniversary is the reason for his detention.

This year, it seems all known critics had to do is talk about Tiananmen Square to get whisked away by state-sponsored thugs. The commemoration has come with the toughest crackdown possibly since 1989, people in Beijing say. The charge levelled at the “dissidents” who have been detained is a new high in the party’s history of inadvertent tragi-comedy: “picking quarrels and causing a nuisance”.

It is doubtless unrelated but worth noting that Guo Jian disappeared only a day after Australia embraced Japan’s defence ambitions at the Shangri-La Dialogue in Singapore and was part of a joint statement issued by the United States and Japan against China’s aggressive actions in the East and South China Seas.

It’s fair to say that any goodwill Australia may have built with Beijing over the search for Malaysian Airlines flight MH370 collapsed like a house of sand at the weekend. Australia’s name will be poison once more in the party’s fortress-like enclave of Zhongnanhai in central Beijing.

DFAT said in a statement:

“The Australian Embassy in Beijing has contacted Chinese authorities to seek further information on the reported detention of Mr Guo Jian and to underline our strong interest in the matter. The Australian Government stands ready to extend all possible consular assistance to Mr Guo.”

A start, but hopefully only the first step. Here is Prime Minister Tony Abbott’s chance to prove that he is prepared to stand up to Beijing all by himself, without his Pacific allies for cover. Or will he allow the rights of yet another Australian citizen in China to be trampled as Canberra pussyfoots around. The last government soft-pedalled in the disputes over Rio Tinto salesman Stern Hu and Guangzhou entrepreneurs Matthew Ng and Charlotte Chou. That strategy proved to be delusional — all three are now languishing in Chinese jails.

Tony Abbott must insist on Guo Jian’s immediate release.

• Michael Sainsbury was China correspondent for The Australian newspaper from 2009-2012, then China bureau chief for the Daily Mail until May 2013.