Twelve years after Chinese troops mowed down student protesters around Tiananmen Square, memories of the infamous massacre have faded with the Chinese public but continue to plague China's leaders.
The anniversary passed quietly today with no hint of public protest save the vain annual appeal by relatives of the victims for an official investigation into the killings.
But the ghosts of June 4th, 1989, have returned to haunt the leadership this year following publication of a book claiming to document the internal debates which led to the crackdown.
Last week, authorities detained six dissidents to warn them not to take part in commemorative activities, the Hong Kong-based Information Center for Human Rights and Democracy reported.
Yesterday, a Foreign Ministry official telephoned foreign news organisations to warn them against "illegal reporting" -- which strictly speaking covers visits to Tiananmen Square and unapproved interviews.
And political comments were quickly removed from Internet chatrooms and bulletin boards today.
The only protest in mainland China came from the mothers of demonstrators killed in the massacre.
They renewed their appeal for an investigation into the role of then Premier Li Peng, now China's parliament chief and number two in the Communist Party hierarchy.
"The identity of those who bear criminal responsibility for the bloody massacre has been revealed to the public eye: their names will live forever as symbols of infamy in the annals of history," the Tiananmen Mothers said in an open letter.
The mothers also thanked the Chinese compiler of the controversial book, the " Tiananmen Papers" for helping to shed light on the events of June 1989.
In an interview with CNN broadcast yesterday, the man known only by his pseudonym Zhang Liang accused Beijing of "vicious and inhumane" tactics in the hunt for the sources behind the book.
The book contains purported transcripts of secret meetings that show a split between moderates led by now disgraced communist party general secretary Zhao Ziyang and hard-liners, including Li Peng.
Some analysts see the book as part of political maneuverings by reformists ahead of a Communist Party congress next year when top leaders, including President Jiang Zemin, are due to step down.