A leading human rights advocacy group has called on China to release scores of prisoners who have been detained on the mainland for supporting pro-democracy protests in Hong Kong, ahead of an international summit of world leaders in Beijing scheduled for next week.

Amnesty International called for the release of 76 people that it says have been detained in mainland China since pro-democracy protests began in Hong Kong on Sept. 28. The detained persons' alleged offenses include posting pictures online with messages of support for the protests, shaving their heads in solidarity, or planning to travel to Hong Kong to participate in demonstrations. Beijing is hosting the 2014 meeting of the Asia-Pacific Economic Cooperation event on Nov. 10-11. Guests will include U.S. President Barack Obama, Chinese President Xi Jinping and Japanese Prime Minster Shinzo Abe.

“APEC leaders must end their recent silence on the crackdown against mainland Chinese activists expressing support for Hong Kong pro-democracy protesters. Political convenience should not trump principled action,” said Roseann Rife, East Asia Research Director at Amnesty International.

Hong Kong has witnessed massive protests since Sept. 28, following the announcement in August that candidates for the position of the city's chief executive would have to be approved by a nominating committee, widely seen as being stacked with supporters of China's governing Communist Party.

According to Amnesty, 93 people had been detained in mainland China for supporting the Hong Kong protests since they began, but as of Nov. 6, the number of persons in detention had fallen to 76. Some mainland activists have been prevented from traveling to Beijing ahead of the APEC summit. Activists in the capital have also been forced to leave the city ahead of APEC, including prominent activists Hu Shigen and Xiang Li. 

Hong Kong was handed back to Chinese rule from the U.K. in 1997, and the two countries agreed that the city would be given a high degree of autonomy, under a policy China calls "One Country, Two Systems." Pro-democracy lawmakers and activists in the city had expressed expectations that, as part of the handover deal with Britain, China's government would allow the 2017 election for the city's chief executive to be conducted on the basis of universal suffrage, without any political screening from Beijing.

However, in an Aug. 31 ruling, the Standing Committee of China's National People's Congress, the country's main legislative body, said that candidates would have to secure the approval of a nominating committee. Democracy activists in Hong Kong saw the ruling as effectively nullifying any chance of a candidate not approved by the Chinese Communist Party of running for the post of chief executive, the top position in the semiautonomous city's government.

Chinese officials, however, have repeatedly expressed concerns in the media and in meetings with pro-democracy lawmakers from Hong Kong, that allowing candidates not vetted by Beijing to stand would present an open door to the U.S. and U.K. to influence policy in the city, and possibly use it as a base to work against the Chinese government.

Chinese authorities have gone to great lengths to ensure the success of the high-profile APEC summit. They have issued instructions for polluting factories around the city to close, introduced strict traffic controls, and declared a public holiday for public schools and many businesses, in an effort to reduce the notorious levels of smog that normally shroud the Chinese capital, according to a report from Voice Of America