The petition from leading intellectuals last week was a plea for tolerance. Instead, the Chinese government responded by detaining five respected dissidents, including Wang Dan, the 1989 student leader, who was picked up by police at his home yesterday afternoon.
Mr Wang and Huang Xiang, detained last week, were among 45 academics, intellectuals and activists who signed the petition, calling for the release of Chinese imprisoned for their opinions, including those sentenced after the June 1989 pro-democracy movement. Mr Huang, a poet, was picked up before dawn on Thursday.
The ritual annual swoop on dissidents in the run-up to the 4 June anniversary of the bloody crackdown in Tiananmen Square appears to be in full swing. Normally opposition figures are taken into custody or encouraged to leave Peking for a few weeks. Security has been tightened across the city.
One of the most vocal dissidents still at large, Mr Wang is regularly taken in for questioning and is under close surveillance.
Other detentions last week, which emerged only at the weekend, were of Wang Xizhe, an activist from the Democracy Wall era, who was released on parole in February 1993 after serving nearly 12 years of a 14-year sentence for "counter-revolutionary propaganda", and Liu Xiaobo, a literary critic who was imprisoned after June 1989.
Mr Liu was a signatory of two petitions this year to the National People's Congress calling for greater democracy and the rule of law.
The government is apprehensive ahead of this year's anniversary, even though the number of dissidents not in detention is small. Last week's petition will have added to its anxiety: the 45 signatories crossed the generations and included Wang Ganchang, 88, an eminent scientist and father of China's nuclear bomb. Evidence that a network of contacts has been established across such a range of opposition voices must concern the government as it prepares for the death, unlikely to be long delayed, of the paramount leader, Deng Xiaoping.
The author of last week's petition, Xu Liangying, 75, said yesterday: "The government is scared to death. But what are they scared of? ... We have no plans to stage demonstrations, we have never said we want to stage a demonstration. All we are asking for is tolerance."
There are also signs of top-level manoeuvrings ahead of Mr Deng's death. President Jiang Zemin is apparently masterminding a purge of potential hardline opponents at the heart of the Communist Party. The latest victim is Yuan Mu, replaced as head of the State Council's Research Centre. He was a strong proponent of the 1989 crackdown. Another hardliner, Chen Xitong, "resigned" last month as party head in Peking.