In Beijing's Tiananmen Square, five Falun Gong members attempted to raise a protest banner Monday but were quickly stopped by uniformed and plainclothes police stationed in the square, the site of frequent protests by the group since the communist government outlawed it five months ago.
Police questioned many other visitors to the vast plaza and led several dozen into waiting blue-and-white police vans.
The prison sentences were handed down Sunday at the conclusion of a one-day trial. Judges found the four Falun Gong leaders guilty of organizing and using an "evil cult" to undermine state law, saying the movement had illegally obtained and disseminated state secrets.
The judges also concluded that Falun Gong's unorthodox health beliefs have led to as many as 1,400 deaths.
Li Chang and Wang Zhiwen were sentenced to 18 years and 16 years in prison, respectively -- among the harshest sentences given to political or religious dissenters in China this decade, the Associated Press reported. Ji Liewu and Yao Jie were sentenced to 12 years and seven years, respectively.
"I'm extremely angry," said Wang Xiaodan, Wang Zhiwen's 20-year-old daughter, who now lives in the United States. The government's "inflexibility, its inability to recognize its mistakes, makes people furious."
Falun Gong preaches a mix of meditation and physical exercises drawn form Taoist, Buddhist and traditional Chinese beliefs. The movement, which has millions of adherents in China and elsewhere, maintains it has no political agenda and only seeks to promote good health and moral living.
However, Chinese officials who maintain tight control over all forms of religious and political expression view the movement's hold over its followers as a threat and have sought to destroy the group.