Hongkongers are among hundreds of thousands of people who have signed a global petition demanding Beijing release Liu Xiaobo - the only Nobel peace laureate in jail and the world's most prominent political prisoner.
The online campaign was launched by Archbishop Desmond Tutu, a fellow Nobel laureate. By 4pm yesterday, it had collected more than 422,000 signatures, including those of about 140 Nobel laureates.
The petition calls on president-in-waiting Xi Jinping to release Liu, who has been in jail since December 24, 2009, and his wife Liu Xia , who has been under house arrest since October 2010.
"This flagrant violation of the basic right to due process and free expression must be publicly and forcefully confronted by the international community," Tutu says in the petition, which he launched late last year.
Liu, one of the authors of the Charter 08 manifesto, which calls for democracy on the mainland, is serving an 11-year jail term handed down in 2009 for "inciting subversion of state power".
He was awarded the Nobel Peace Prize in 2010.
*Patrick Poon Kar-wai, the Hong Kong representative of Friends of Liu Xiaobo, said Amnesty International would submit the petition, signed by people in 130 countries, to the central government's liaison office. He called for more Hongkongers to join the campaign as "the threat to freedom of expression could otherwise spread to Hong Kong".
The petition will also be submitted to Chinese embassies and diplomatic missions in New York, Paris, Berlin and London.
In Taiwan, Wuer Kaixi, a leader of the 1989 Tiananmen protests and one of those who signed the petition, urged President Ma Ying-jeou to raise the issue of the petition with Xi.
"Hopefully, through the petition, President Ma could do something that would help the Chinese government's release of Liu Xiaobo and his wife," he said.
Ma has previously called on the Beijing government to release Liu, who was the third person to win the Nobel Peace Prize while incarcerated, following Myanmar's Aung San Suu Kyi in 1991 - when she was under house arrest - and German pacifist Carl von Ossietzky in 1935, who was near death after being thrown into a concentration camp.
Additional reporting by Agence France-Presse
*Correction: An earlier version suggested the petition would be submitted by the group Friends of Liu Xiaobo. The text has been clarified to say Amnesty International will deliver the petition signatures to the central government's liaison office.