By Richard Spencer

BEIJING -- China's top security official insisted yesterday that tighter controls were needed to stop next year's Olympic Games from being disrupted by "hostile forces," including foreigners.

When Beijing was awarded the games seven years ago, the International Olympic Committee (IOC) said the decision would help to bring greater freedom to China's politics. But since then, despite changes in the country forced on it by globalization and the Internet, there has been a crackdown on political opposition.

In the latest in a series of attempts to play down the chances of political liberalization, Zhou Yongkang, the minister for public security, said police should "defend political and social stability."

"We must strike hard at hostile forces both in and outside the nation," he said in a speech given Monday and published in the state press yesterday.

He went on to give a list of those the state now regards as its principal enemies. These included regular targets such as Falun Gong, the banned religious group whose sit-down protests in the past have triggered fear in the authorities, and "splitism and religious extremism."

This is a catch-all phrase for anyone supporting independence or greater autonomy for Tibet, Xinjiang or Taiwan. The government fears that free-Tibet campaigners in particular could use the games as an opportunity to boost international sympathy for their cause.

Tibetan activists and representatives of the Uighurs, the Muslim ethnic group that lives in Xinjiang, are regularly harassed and jailed, with well-documented claims of torture.

The reference to "hostile forces outside the nation" may refer to overseas supporters of these groups. But the government has also focused in the last two years on the role that international human rights and pro-democracy organizations played in "color revolutions" in Eastern Europe and Central Asia.

"We must firmly grasp the changes developing in the international and domestic situation," Mr. Zhou said.

When the games were awarded to Beijing in 2001, one of the reasons given by the IOC was the opportunity that it would give for improving human rights.

Since then, Web sites have given a voice to individuals' complaints about official corruption and social inequality, while in accordance with IOC demands, heavy restrictions on reporting by foreign journalists were lifted on Jan. 1.

But the government is keen to insist that there is no chance of an end to single-party authority.

It is nervous of the example set by neighboring South Korea, whose military dictatorship was forced to reintroduce democracy after a series of demonstrations in the run-up to the 1988 Olympics in Seoul.

It also wants to ensure that dissidents, human rights activists and other pressure groups inside the country know that there are limits to how far they can push for greater freedoms just because they know the outside world is watching.

"There's no doubt that activists in China are increasingly aware of the fact that the Olympics gives them an opportunity to gain more space, to push the envelope precisely because they will be protected by this intense spotlight," said Nicholas Becquelin of Human Rights Watch in Hong Kong.

"From the police perspective, this is essentially a prevention exercise."