Uniformed and plain-clothed security personnel were out in force on Tiananmen Square, Thursday, the 20th anniversary of a bloody crackdown against demonstrators who had been protesting there for greater political freedom and against official corruption.
Police were everywhere around Tiananmen Square.
They checked foreigners' bags and prevented foreign journalists from actually going onto the square. Uniformed agents patrolled in pairs. Others, dressed in plain clothes, mingled in with the crowds of tourists.
Chinese Foreign Ministry spokesman Qin Gang was asked at a regular briefing why the security presence was so visibly increased.
Qin only gave a very brief answer, saying the square is stable, as usual.
Two of the best known government critics - former senior government official Bao Tong and activist Ding Zilin - could not be reached, amid reports that they had been ordered to leave Beijing because of the June Fourth anniversary.
In an interview earlier this year, Bao Tong said he is confident the government will have to reassess its verdict that the 1989 Tiananmen Square protests were counter-revolutionary and, therefore, criminal.
Bao says, if the protests are reassessed, it would be like a rebirth for China and a restoration of human rights for the Chinese people.
Bao is the highest-ranking person to have spent time in jail for supporting those in the government who, at the time, wanted to talk to the students, not shoot them. He was director of the Communist Party's political reform office.
Ding Zilin is a retired professor who has a personal stake in pushing for an official accounting of what happened 20 years ago. Her 17-year-old son was killed by a stray bullet near Tiananmen Square, in the early hours of June Fourth, 1989.
Ding says everything seems like it just happened yesterday. She says the sorrow and pain grow stronger each year, as she gets older.
She helped found a group called Tiananmen Mothers, made up of parents whose children were killed in the crackdown. She says the group's most powerful cohesive force is a sense of shared tragedy.
Ding says the mothers did not know each other, 20 years ago. Now, they are bound by the memories of their children.
The group has issued what has almost become an annual tradition - an open letter calling for an official investigation, compensation to the victims' families and punishment for those responsible.
The Chinese spokesman did not directly answer repeated questions as to the official death toll for the 1989 crackdown. He indicated the government is not planning to reconsider its verdict, at least not any time soon.