Human Rights Watch released a scathing report Wednesday slamming the Chinese government for crafting an "Orwellian high-tech surveillance state" at home and deploying its growing economic clout to silence its critics overseas, while an official with the group criticized Japan's response to alleged rights abuses as "lukewarm."

The report, which covers the global human rights situation but begins with a keynote essay by the group's executive director, condemned China's treatment of Uighur Muslims in its far-west Xinjiang region and warned that China's growing political influence and efforts to censor people abroad poses an "existential threat to the international human rights system."

Beijing has previously criticized HRW over its investigations on surveillance technology and what China calls "re-education camps" in Xinjiang. The United Nations estimates roughly 1 million Uighurs have been detained in Xinjiang. Beijing denies any mistreatment of Uighurs or others in the region, saying it is providing vocational training to help stamp out Islamist extremism and separatism, and to teach new skills.