At last week's 19th party congress, China's Communist Party announced a new era under President Xi Jinping.
But Amnesty International spokesman Patrick Poon, who is based in Hong Kong, claims it is set to bring about more restrictions on society.
"That only means there will be more control on civil society and human rights defenders," Mr Poon said.
Human rights groups are concerned about the situation surrounding Hong Kong bookseller Gui Minhai, who disappeared from his Thailand home in 2015.
His friends say he is now only "half-free" after being released from custody last week, as they fear he is being closely monitored by security officials in eastern China.
"It's very much unclear about whether he's under surveillance of the police, and whether he will eventually be successful in returning to his home in Germany," Mr Poon said.
Activists have compared his treatment to Liu Xia, the wife of Liu Xiaobo, who has not been since her husband's death in July.
Hong Kong bookseller Gui Minhai making an apparently staged confession on state television after his arrest in 2015. Source: Reuters
Liu Xiaobo, a Chinese dissident and Nobel Peace Prize winner, was arrested in 2008 and died in hospital, never regaining his freedom.
Life under police watch
By day police watch human rights activist Zhou Li's Beijing home. It is only at night when they leave that she can speak to journalists.
But she says it is getting harder and more risky to do that now that Mr Xi has begun his second term as leader.
"Over the next five years the control will be stricter. Our space for survival, for movement and free speech will be smaller," she said.
Ms Li has been in and out of jail on multiple occasions after speaking up for those who have had their rights infringed upon and has also promoted democracy in China online.
"They want to torture you and wear you down spiritually," she said, referring to a time she says she was held for questioning without any sleep for 72 hours.
She is no longer prepared to risk speaking out.
"Because I have a family, a husband, elders. I can’t continue. I try my best in the space I have to help someone, without crossing the line."
China already employs people to monitor the internet and censor criticism of the government or comments about sensitive issues.
"The space for free speech is smaller. Control over online speech is stricter," Ms Li said.
