Chinese authorities are clamping down on rights activists trying to hold public memorials for the victims of the Tiananmen military crackdown on student-led protests in June, 1989, in which hundreds of people were believed killed.
A group of around 200 petitioners in Shanghai were dispersed by police after they tried to hold a memorial event in one of the city's parks, participants said.
"We were all dressed in white clothes and shoes," said one participant, Tan Lanying, referring to the traditional Chinese mourning color. "We went to the Putuo district park to hold a memorial."
But she said the police were waiting for the group, and had sealed off all of the park gates.
"They ... wouldn't let us go in, so there was no way we could go ahead with the event," Tan said. "The police knew about it all in advance."
She said the petitioners would hold the event "another day."
Authorities in the Chinese capital have boosted security ahead of the June 4 anniversary of the 1989 military crackdown on student-led pro-democracy demonstrations in the heart of Beijing.
No form of public memorial has ever been held for those who died when the People’s Liberation Army cleared thousands of protesters from the center of the city.
Instead, police regularly clamp down on any form of public protest or discontent at this time of year.
The Tiananmen Mothers, a group representing the victims of the crackdown, including those who died or were maimed, accused the government this week of offering secret compensation deals to some victims.
The group, headed by retired Beijing University professor Ding Zilin, has tried to compile lists of victims and the places that they died, as well as calling annually for an official reappraisal of the protests and the crackdown which ended them.
Another group of petitioners from Shanghai traveled to Beijing at the end of last month, hoping to meet up with a larger group already in the capital and stage a "June 4 Memorial Activity," petitioners said.
"There are a lot of people still in Beijing," said Shanghai-based petitioner Chen Qiyong. "I heard them say over at the municipal government buildings today that another group was on its way there."
Several hundred Shanghai activists, many of whom have pursued complaints against government officials for years with no redress, had been detained in Tianjin and Shijiazhuang after trying to get into Beijing, where security forces have built sentry points on major routes into the city.
"In Beijing, we want to get to Tiananmen Square ... to honor the memory of the student martyrs," Tan said. "We petitioners are following in their footsteps, and there is no going back."
"We want freedom and we want democracy."
Tan said activists were planning memorial events in Beijing and Shanghai, in case the Beijing event was disrupted by police in advance.
Beijing residents say this year's clampdown is particularly harsh, coming hard on the heels of dozens of arrests of dissidents and lawyers amid fears of a "Jasmine" revolution inspired by recent uprisings in the Middle East.
This year also marks the 90th anniversary of the founding of the ruling Chinese Communist Party on July 1, with the authorities ordering a slew of patriotic TV programs and public celebrations.
Reported by Fang Yuan for RFA's Mandarin service. Translated and written in English by Luisetta Mudie.