China is keeping democracy campaigners and survivors of the 1989 Tiananmen Square crackdown under tight surveillance to prevent them from publicly mourning late Communist Party chief Zhao Ziyang.
Mr Zhao, purged for opposing the army massacre of hundreds, perhaps thousands, of student protesters on June 4th, 1989, died in a Beijing hospital in January at the age of 85.
His successors had tried to airbrush him from history by keeping him under house arrest for 15 years, fearing he would evoke memories of the bloodbath and spark unrest by jobless workers and poor farmers envious of wealthy urban residents.
Chinese traditionally flock to cemeteries on the festival of Qing Ming (Tomb-Sweeping Day) to burn incense and ghost money and offer sacrificial food in memory of deceased relatives. This year authorities fear the occasion could be used to publicly mourn Mr Zhao.
As premier in the 1980s, Mr Zhao began market reforms that turned China from a centrally planned backwater into a fledgling economic powerhouse. Political reforms he set in motion have stalled since his downfall.
Mr Zhao's family welcomed mourners to visit his Beijing home on Qing Ming, the Hong Kong-based Information Centre for Human Rights and Democracy said in a statement.