Chinese authorities detained nearly 1,000 human rights defenders in 2014, an advocacy group said Monday, accusing President Xi Jinping's government of setting China's "worst record of human rights violations since the mid-1990s".

The figure nears the number detained in the previous two years combined, the overseas-based advocacy group Chinese Human Rights Defenders (CHRD) said in its annual report.

"Since Xi came to power, authorities have pursued a relentless and ruthless assault on fundamental liberties to tighten the stranglehold on the rapidly shrinking space of civil society, targeting human rights defenders, the messengers of human rights," the group wrote.

"In greater numbers than at any time since the mid-1990s, in the aftermath of the Tiananmen Massacre, activists, lawyers, journalists, and liberal intellectuals were locked up, put under house arrest, blocked from speaking out, or essentially forced into exile abroad," it said.

The group recorded 955 cases of activists and others it describes as rights defenders having been deprived of their freedom in 2014. The total for the previous two years was 1,160.

The report comes shortly after five women's rights campaigners were detained in Beijing for planning protests against sexual harassment on International Women's Day.

Amnesty International decried the detentions as "chilling", and the European Union has demanded their release.

Since taking office as Communist chief in 2012, Xi has overseen a campaign against government critics with hundreds detained or jailed.

China maintains that it safeguards its citizens' legal rights, including freedom of assembly, expression, religion and the press.

Yet, according to the CHRD report, "the second year under Xi Jinping's rule was even more draconian than the first".

More than 200 activists, lawyers, journalists and others were detained surrounding the 25th anniversary of the Tiananmen crackdown in June and Hong Kong's pro-democracy Occupy Central campaign in the autumn.

In addition, more human rights lawyers were likely to have been detained or prosecuted in 2014 "than in any year since the early 2000s, when such lawyers first came onto the scene", CHRD said.

"Those who demanded to exercise their fundamental rights or challenge the increasingly repressive system faced government retaliation, including the use of torture, arbitrary detention, enforced disappearance, intimidation and other forms of mistreatment," the group wrote.

It described Xi as having "spearheaded an ideological shift that harkens back to the Maoist era".

In January, the New York-based group Human Rights Watch said in its annual report that the ruling Communist Party has "unleashed an extraordinary assault on basic human rights and their defenders with a ferocity unseen in recent years".

It added that recent developments in China are "an alarming sign given that the current leadership will likely remain in power through 2023".