Taiwanese Vice President Annette Lu accused Hong Kong on Saturday of mistreating and denying entry to Taiwanese followers of the Falun Gong spiritual movement.
More than 400 Taiwanese members of the group banned in China as a subversive organization and "evil cult" tried to enter Hong Kong carrying valid travel documents Feb. 21-22, the group's Taiwanese chapter said.
But immigration officials at Hong Kong's airport refused entry to at least 80 of them, citing security concerns, the group said.
Nine members complained that the officials and police used violence to force them onto a flight back to Taiwan.
"This violent treatment will hurt our citizens' freedom of religion and freedom to travel," Lu said at a meeting of a national human rights committee that she chairs.
"Over 4 million Taiwanese visit Hong Kong annually, and this kind of incident could happen again," she warned.
Lu said the treatment of the Taiwanese Falun Gong followers showed Hong Kong's human rights situation had deteriorated since the former British colony's return to China in 1997. Hong Kong still has its own legal system and Western-style freedoms.
In Hong Kong, a government spokesman said the immigration department has dealt with all entry applications in accordance with Hong Kong laws and policies.
"We will continue to welcome Taiwanese visitors but we will always exercise our statutory authority to allow or disallow entry of people from any jurisdiction according to our laws," said the official, who issued the comment on condition of anonymity.
The Taiwanese vice president also told Falun Gong members she supported their efforts to publicize China's use of violence and terrorism in repressing human rights.
The meditation group is outlawed in mainland China, but it is free to practice, and protest, in Hong Kong.
Taiwan and China split amid civil war in 1949, and Beijing has threatened to use force to reunify the two sides.