Beijing -- With just days to go before the 30th anniversary of the Tiananmen Square massacre of June 4, 1989, it was business as usual in Beijing. That means increased censorship, and detentions.

On Friday, New York-based Human Rights Watch (HRW) published a list of names associated with the pro-democracy protests of 1989. Some of the people on the list have already been jailed, recently placed under house arrest or forced to go on "vacation" far from the capital, as the country approaches the grim anniversary that its government will barely acknowledge.

This list includes a non-governmental group, called the Tiananmen Mothers, made up of relatives of people killed in the ultimately-failed push for democratic freedoms in China. There are no official numbers, but estimates of how many people were killed in and around Tiananmen on that day range from a few hundred, to a few thousand.

Also on the HRW list, an independent filmmaker who tweeted a photo alluding to the massacre and two activist brothers who produced an alcohol called "Eight Liquor Six Four." Spoken out loud and in Chinese, the words sound exactly like the date Beijing cracked down: June 4, 1989.

Speaking on Thursday in Washington U.S. State Department spokesperson Morgan Ortagus said the U.S. government was aware of the reported arrests in China ahead of the anniversary, and "it couldn't be more troubling."

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"We shouldn't forget that this was a full-on massacre of peaceful protesters that occurred," she said, adding: "I think the U.S. has called for and we will continue to call for, as have others in the international community, a full public accounting for those killed, detained, and missing. We want those released who have been jailed for striving to keep the memory of Tiananmen Square alive."

Detaining people is just one way Beijing has silenced domestic critics over the past three decades.

Online, events surrounding Tiananmen Square have been labeled the most censored topics on China's tightly-controlled internet. More than 3,200 words that reference the massacre have been censored, according to a joint survey released this year by the University of Toronto and the University of Hong Kong.

Chinese live video streaming sites have, perhaps not coincidentally, announced they would be "updating" their systems over the next several days, preventing users from creating new accounts or posting comments in real time.

Limited acknowledgement of history

On Friday, China's Defense Ministry did make one small acknowledgment of the Tiananmen crackdown, pushing back against a Reuters reporter's use of the word "suppression" in a question, to describe the military's reaction to the pro-democracy protests.

"First of all, a clarification. I don't agree with you for using the word 'suppression,'" Defense Ministry spokesman Wu Qian said, according to Reuters. Wu added, without further clarification, that: "In the last 30 years, the course of China's reforms, development and stability, the successes we have achieved have already answered this question."

While there are no anti-government protests around the anniversary expected on mainland China, two places on Chinese soil are able to commemorate and remember the dark episode from the nation's history: the special administrative regions of Hong Kong and Macau.

Former British colony Hong Kong, and Macau, a former Portuguese enclave, both have governing administrations separate, but not at all fully independent of Beijing. Last week in Hong Kong, an estimated 2,000 people took to the streets demanding Beijing take responsibility for the 1989 crackdown. The Chinese territory has held an annual mass candlelight vigil, attended by tens of thousands of people, every year since the Tiananmen Square uprising. Last year, an estimated 100,000 people showed up.

On the mainland, June 4 is expected to be a quiet day again this year. On Tiananmen Square itself, as in years past, there will be no commemorations, no flowers and no protestors.

But there will be plenty of authorities, on high alert and ready to crack down again.