Swarms of plainclothes police took away four foreign activists who tried to unfurl a Tibetan flag outside the main Olympics venue on Thursday, squelching the latest attempt to demonstrate during the Beijing Games.
The detentions came a day after authorities warned two elderly Chinese women who applied to protest the loss of their homes during the games that they would be sent to a labor camp for a year.
Early Thursday, police seized four foreign activists protesting Chinese rule in Tibet as they unfurled a Tibetan flag and shouted "Free Tibet" south of the National Stadium, the New York-based Students for a Free Tibet said.
The group put the number of police at 50. A spokeswoman for the Beijing Public Security Bureau declined comment.
"The fact that there were so many undercover police following them just made them go with the action urgently," said Kate Woznow, the group's campaigns director.
Two Associated Press photographers were roughed up by plainclothes security officers, forced into cars and taken to a nearby building where they were questioned before being released. Memory cards from their cameras were confiscated.
The four activists were identified by Students for a Free Tibet as Tibetan-German Florien Norbu Gyanatshang, 30; Mandie McKeown, 41, of Britain; and Americans Jeremy Wells, 38 and John Watterberg, 30.
The whereabouts of the activists was not known. Other foreigners from the group who have staged demonstrations before and during the games have been quickly deported from China.
The rough treatment and intimidation being meted out to foreigners and elderly Chinese underscores the authorities' determination to prevent any disruption during the Olympics, even though the games' organizers last month said demonstrations would be allowed in designated areas.
But the games have provided a tempting spotlight to several protesters.
The two elderly Chinese women _ Wu Dianyuan, 79, and her neighbor Wang Xiuying, 77 _ were still at home three days after being officially notified they would have to serve a yearlong term of re-education through labor.
They were under surveillance by a neighborhood watch group, said Li Xuehui, Wu's son.
Li said no cause was given for the order to imprison the pair. Activists said the order was an intimidation tactic.
The Public Security Bureau had no immediate comment. A spokeswoman for the Beijing re-education through labor bureau said, "We have no records of these two names in our system."
Wu and Wang had repeatedly tried to apply for permission to hold a protest at one of three areas designated by the government as available for demonstrations during the games, which end Sunday.
Beijing has used the existence of the protest areas as a way to defend its promise to improve human rights in China that was crucial to its bid to win the games.
Some 77 applications were lodged to hold protests, none went ahead. Rights groups say the zones were just a way for the Chinese government to put on an appearance of complying with international standards. A handful who sought a permit to demonstrate was taken away by security officials, rights groups said.
The re-education system, in place since 1957, allows police to sidestep the need for a criminal trial or a formal charge and directly send people to prison for up to four years to perform penal labor.
Critics say it is misused to detain political or religious activists, and violates rights.