BEIJING (AP) - Chinese police tore up a protester's poster and detained at least two people on Beijing's Tiananmen Square on Sunday as the country marked 17 years since local troops crushed a pro-democracy demonstration in the public space.

An elderly woman tried to pull out a poster with apparently political material written on it, but police ripped it up and then took her away in a van.

A farmer tried to stage a protest apparently unrelated to the 1989 crackdown, but he also was taken away in a van.

After dawn, a group of tourists tried to open a banner while posing for a photo, catching the attention of police, who quickly forced them to put the nonpolitical material away. They were not detained.

Discussion of the crackdown is still taboo in China outside of the semiautonomous regions of Hong Kong and Macau. Chinese television news and major newspapers did not mention the anniversary.

In Hong Kong, several hundred people holding candles gathered at Victoria Park, creating a sea of lights covering four soccer fields.

"I hope the Chinese government will recognize this dark history," Eric Lau, 14, said.

Retiree Yan San, 74, said he has attended the annual commemoration in Hong Kong since its debut in 1990.

"I have persisted in coming here for 17 years because I love freedom and democracy," he said.

China's authoritarian government has stood by the suppression of what it has called "counterrevolutionary" riots, saying it preserved social stability and paved the way for economic growth.

The events of June 4, 1989, shocked Hong Kongers at a time when the territory was still a British colony but preparing to return to Chinese sovereignty in 1997. The bloody suppression fueled fears that Beijing would extend its authoritarian rule to Hong Kong.

Chinese police monitored Tiananmen Square closely Sunday.

About 2,000 police were on guard in and around Beijing's "petitioner's village," a cluster of cheap hostels popular with people from the provinces who have come to the capital to complain to the central government.

Wang Dan, a leader in the 1989 protests who was jailed and then exiled to the United States, said in an article published in Hong Kong's Ming Pao newspaper Sunday that he holds out hope China will loosen its political controls.

"Although so far we can't see any loosening, personally I'm confident that day will come," he said. "Until the government reverses its position (on the 1989 protests), ordinary people won't easily forget the crackdown."

Hong Kong leader Donald Tsang, while in China's southwestern Yunnan province to attend a regional cooperation conference, urged his fellow citizens to look at the Tiananmen crackdown practically.

"Mainland China has undergone a level of change that has gained the world's attention in the past 17 years. These changes have brought much prosperity to Hong Kong ... so Hong Kong people can make an objective judgment," Tsang said.

Hong Kong Cardinal Joseph Zen, a fierce democracy advocate, disagreed with Tsang.

"How can we let it go? Should we just let it slide, forgive, pretend nothing happened? This is irresponsible. The successors of those responsible for the June 4 incident should give an explanation," Zen said.

Associated Press reporters Marco Lui and Min Lee in Hong Kong contributed to this report.

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