(Note: Erin Hale in Hong Kong and Yu-Tzu Chiu in Taipei)
Hong Kong (dpa) - Thousands of Hong Kong residents gathered in the rain and evening darkness of Victoria Park on Monday for a candlelight vigil in honour of those killed during China's crackdown on the Tiananmen Square protests in 1989.
Families of the victims accused China's communist leadership of using "a bloody massacre to ensure the so-called stability of the country and the smooth progress of reform."
In an open letter to Chinese President Xi Jinping, the Tiananmen Mothers activist group wrote that the actions taken by China's military 29 years ago amounted to an "anti-human crime" and that the families of the victims deserved "truth, compensation, and accountability" from Beijing.
Protests on Beijing's Tiananmen Square in 1989 were triggered by the death of reformist leader Hu Yaobang on April 15 that year. Demonstrations escalated through the month of May, eventually including demands for greater political freedom and democracy in China.
On the eve of June 4, tanks rolled onto the protest sites and soldiers opened fire. An unknown number of people died in the crackdown. Estimates range from hundreds to thousands of fatalities, but the official number remains unknown.
Information on the protests and the ensuing crackdown is censored year-round in China, although censorship increases around the anniversary.
On Sunday, US Secretary of State Mike Pompeo called for a "full public accounting of those killed, detained or missing" at the student protest.
Chinese authorities rebuked the US calls for transparency and decried what they called foreign interference.
"The United States issued a so-called statement year after year, made groundless accusations towards the Chinese government and interfered in China's internal affairs," Foreign Ministry spokesman Hua Chunying said on Monday.
"We urge the United States to abandon its prejudices, correct its mistakes, stop making irresponsible remarks, and stop interfering in China's internal affairs."
The mention of the June 4 anniversary date has been censored on social media platform Sina Weibo, according to monitor FreeWeibo. The mention of the "US Embassy" was also censored following Pompeo's comments.
Hong Kong residents have traditionally held an annual candlelight vigil to remember the Tiananmen victims – a tradition that began while the city was still a British colony.
"It has been the most important and long-lasting social movement in Hong Kong," said organiser Richard Tsoi, vice-chairman of the Hong Kong Alliance in Support of Patriotic Democratic Movements in China.
Participation in past vigils have ranged from 20,000 people to 80,000 people, according to police.
Hong Kong, a Special Administrative Region of China since 1997, was known for helping hundreds of Tiananmen Square leaders escape China in "Operation Yellowbird" in the summer of 1989.
On Monday, Taiwanese President Tsai Ing-wen advocated for transparency about the Tiananmen protests in a Facebook post that was written in a simplified Chinese used in mainland China.
"Should Beijing face up to the June 4 incident and admit its exertion of state violence in the crackdown, the tragedy would be transformed into a foundation for democratic reform in China," Tsai said.
In Taipei, hundreds of democratic advocates held a vigil to commemorate Tiananmen victims and repeated their call on Beijing to release Lee Ming-che, a Taiwanese democracy advocate who has been detained in China for more than a year.
Wu Jen Hwa, who participated in the 1989 protests and witnessed the crackdown, said at the gathering in Taipei that, based on his research, the death toll could be as high as 2,000, with thousands of others injured.
"Sadly, 29 years later, the Chinese government still continues to hide the truth," said Wu, who currently teaches at Taiwan's universities as a visiting scholar.