China's respect for freedom of religion remained "poor" last year, most notably for members of underground groups such as the outlawed Falungong movement, the United States charged.
Repression was widespread, and there were "numerous credible reports" of the abuse or killing of Falungong followers by police, the State Department said in its annual report on international religious freedom.
Religious repression in Tibet also remained high, said the lengthy chapter on China, which was swiftly rejected as "groundless" by Beijing.
"During the period covered by this report, the government's respect for religious freedom and freedom of conscience remained poor, especially for members of some unregistered religious groups and spiritual movements such as the Falungong," the International Religious Freedom Report 2002 said.
Beijing "continued its repression of the Falungong spiritual movement and of cults in general", it added.
Falungong leaders say that hundreds of practitioners of the Buddhist- and Taoist-based group, which was banned on the mainland in 1999 as a so-called "evil cult", have been killed in custody.
Beijing rejects this, insisting that those who have died committed suicide or refused medical treatment.
According to the report's authors, China also continued a crackdown on unregistered churches, temples, and mosques, while adding that the levels of harassment varied widely from place to place.
"Members of some unregistered religious groups, including Protestant and Catholic groups, were subjected to increased restrictions, including, in some cases, intimidation, harassment, and detention," it said.
However in some places, "government supervision of religious activity was minimal, and registered and unregistered churches existed openly side by side and were treated similarly."
China officially allows places of worship to operate only if they are affiliated to state-registered "patriotic" organisations, which in the case of the Catholic Church recognises the authority of Beijing and not the Vatican.
In Tibet, treatment of the region's indigenous Buddhist religion which has the exiled Dalai Lama as its head, improved slightly against 2001, the report said.
"However, the level of repression in Tibet remained high and the government's record of respect for religious freedom remained poor", it said.
China's foreign ministry rejected the report out of hand on Tuesday.
"China's constitution allows for complete freedom of worship. It is a fact that is known to all," said spokeswoman Zhang Qiyue.
"In our view the US is pointing its fingers at other countries' domestic affairs."
The United States has long been vocal on the issue. During a visit to Beijing in February, President George W. Bush used a nationally-televised speech to express a "prayer" for freedom of worship for China's people.