Hong Kong police arrested four people and detained five others Tuesday as authorities sought to stamp out commemorations of the 1989 Tiananmen Square crackdown on pro-democracy demonstrators in mainland China on its 35th anniversary.

Police were out in force patrolling Hong Kong’s Victoria Park, where an annual candlelight vigil had been held until recent years.

As police patrolled the area, including the two closest subway stations, they did not hesitate to take away people who were publicly marking the anniversary.

As the 35th anniversary of Beijing’s Tiananmen Square crackdown neared, Rowena He, a prominent scholar of that bloody chapter of modern China’s history, was busy flying between the United States, Britain and Canada to give a series of talks. Each was aimed at speaking out for those who cannot.

A bipartisan group of lawmakers gathered in the capital today to commemorate the Tiananmen Square Massacre and celebrate the continued struggle for democracy in China.

The event near the steps of the Capitol Building was led by members of the House Select Committee on Strategic Competition with the Chinese Communist Party (CCP) and featured several survivors of the 1989 incident in Tiananmen Square.

Washington marked the anniversary of the 1989 Tiananmen Square crackdown with a series of events and statements on Tuesday, urging Beijing to release political prisoners and hold itself accountable for alleged human rights abuses.

“Today, on the 35th anniversary of the Tiananmen Square massacre, we remember the tens of thousands of peaceful Chinese pro-democracy protesters who were brutally assaulted for standing up for freedom, human rights and an end to corruption,” said US Secretary of State Antony Blinken.

Late into the night on Wednesday, around 11p.m. local time, security staff at the University of Hong Kong surrounded a statue dedicated to the victims of the Tiananmen Square massacre and obscured it with curtains and plastic barriers.

Those in the area could hear the sounds of construction but were not told what was going on. Xinqi Su, Hong Kong correspondent for the Agence France-Presse, said the Pillar of Shame statute was covered up, and she was told not to film. She also said security guards tried to drive her away and wouldn’t tell her what was happening.

Senator Mitt Romney wants answers from Microsoft after the company blocked images and videos around the world of "Tank Man," the unidentified protester during China's brutal crackdown on pro-democracy demonstrations in Beijing's Tiananmen Square on June 4, 1989.

In a letter to Microsoft CEO Satya Nadella provided exclusively to CNN, Romney said he was concerned about how the company's censorship in China could spill over into America.

They had been barred from holding their usual memorial, but that did not mean they would not remember.

They gathered online, to watch a reading of a play about the massacre of pro-democracy demonstrators in Beijing on June 4, 1989. They prowled bookstores, on a scavenger hunt for protest-themed postcards hidden in the stacks. They scribbled the numbers 6 and 4 on their light switches, so that everyday actions would become small acts of defiance.