BEIJING -- At first glance, the several dozen Falun Gong followers who gather to exercise and meditate under a stand of pines in Beijing's Altar of the Sun Park seem no different from everyone else busy keeping fit each morning.
But they are part of something much bigger. Just how big hit Beijing forcefully on Sunday, when more than 10,000 Falun followers held a daylong protest outside the walled compound where China's communist leaders live and work -- the biggest demonstration in the Chinese capital since the Tiananmen Square democracy protests 10 years ago.
Although their agenda seemed modest enough -- a guarantee they could pursue their beliefs free from official interference -- Falun Gong poses a dilemma for China's ruling Communists.
It teaches morality and acceptance, just what the Beijing government likes to see. But, with more members than the Communist Party -- at least 70 million, according to the State Sports Administration -- Falun is also a formidable social network linked by mass loyalty to its founder, Li Hongzhi, a martial arts master who lives in New York.
And some critics fear the group could be a cult.
"There's a real danger to society," said He Zexiu, a physicist who helped design China's hydrogen bomb in the 1960s and who has denounced Falun on state television.
He warns Falun could be a cult manipulated by Li, who founded the group in 1992 while living in his native China. He also denounced the group's call for disciples to eschew all medicine.
Rong Yi, a spokeswoman for the group in the United States, denied Falun is either a cult or anti-government, noting that it teaches good citizenship, can be practiced for free and that its followers can leave the movement any time they choose.
Li Hongzhi lives off royalties from his Falun text and sermon compilations. A Falun web site claims membership of 100 million in China, the United States, Canada, Europe, Australia and Singapore.
Falun Gong (pronounced fah-luhn gung) borrows heavily from Buddhist and Taoist philosophies and styles itself as a school of qigong (pronounced chee-gong), a traditional Chinese practice that uses meditation and martial arts exercises to channel unseen forces and improve health.
Qigong has been enormously popular in China since bans on cultural traditions were lifted in the late 1970s. Nearly every Chinese city dweller at least knows someone who goes to parks or meetings in search of healing and longevity through qigong, according to Nancy Chen, an anthropologist at the University of California at Santa Cruz, who wrote a book on urban life in China.
The government tolerates qigong schools it deems acceptable and suppresses others as superstition. Any attempt to ban all qigong would pit the central government against the large proportion of the population that believes in it.
So far, Falun is under study, and no conclusion has been reached, said Wang Kai, an official in charge of qigong for the State Sports Administration and himself a practitioner of Falun.
Government leaders ordered a ban Monday on all comment or reports by state media concerning Sunday's protest, said a government official who spoke on condition of anonymity.
But some local officials are trying to curb the group, just as they have other organized networks viewed as threats to the communists' authority.
Falun books are hard to publish in China, and police in Tianjin recently roughed up and detained some Falun practitioners who went to a magazine office to protest an article that criticized the group, said Rong, the group's U.S. spokeswoman.
Falun Gong teaches that illness is caused by evil that can be purged. By following the three principles of "truth, compassion and forbearance," clairvoyance and other supernatural powers can be obtained. Those who reach enlightenment will look younger -- with clear skin and fewer wrinkles -- and feel "light all over."
Followers believe Li implants a falun -- a "wheel of law" or miniature of the universe -- into their lower abdomens, where it spins constantly, absorbing and releasing power.
By 7 a.m. on a recent Sunday, more than 800 Falun enthusiasts were lined up in neat rows a dozen deep for exercise in front of a government trade building on the capital's main east-west thoroughfare.
"We have only one teacher, Li Hongzhi," said a practitioner, a Mrs. Liu, standing under Falun's large yellow banners in Altar of the Sun Park. She offered a handout saying "Great Master Li's" teachings would protect followers so that "no harassing from external evils is to be feared."
Chen Zhong, a retiree who practices Falun, said it instills high standards, promotes good deeds and deters crime. He said followers are told not to take medicine and claimed many have been cured of leukemia, hepatitis and other diseases through Falun.
Wang, the government official in charge of qigong, said Falun saves millions of dollars in medical costs and makes people feel so content that they "will do their job happily and can help build up the country."