BEIJING — China's military has deployed tens of thousands of soldiers to safeguard the Olympics from possible terrorist attacks, a senior officer said today, saying the gravest danger came from Muslim radicals in western China.

However, underscoring China's sometimes contradictory approach to such problems, a Xinjiang vice governor speaking separately downplayed the danger, saying such groups were tiny in number and highly disorganized.

"So you can see that these terrorist groups are not that capable of instigating massive sabotage activities as some hostile forces hope to see," Kurexi Maihesuti told reporters.

China has laid on massive security for the games that kick off Aug. 8, as much to prevent protests by political or religious dissidents as to stop crime and terrorism. A 100,000-strong force of police and special forces are safeguarding venues.

Hundreds of thousands of Beijing residents have also been formed into voluntary security patrols.

In addition, a force of 34,000 soldiers has been positioned in Beijing and other cities such as Shanghai that are hosting Olympic events, Senior Col. Tian Yixiang, of the Olympics security command center, told reporters.

"To the Beijing Olympic Games, the biggest threat comes from the East Turkistan terrorist organization," Tian said, using an alternate name for Xinjiang used by radical anti-government groups.

A secondary threat came from Tibetan separatists who Beijing accuses of orchestrating a wave of violent protests in western China this spring, Tian said. "These forces are trying all means to sabotage the Beijing Olympic Games," Tian said.

Beijing claims to have foiled a series of plots by members of Xinjiang's main Uighur ethnic group that it says targeted the Olympics, detaining 82 alleged Islamic terrorists and separatists in a major crackdown.

Few details have been given and no evidence shown, although terror experts say insurgents based along the border with Afghanistan and Pakistan have a limited capability to launch such attacks.

Meanwhile, at the Olympic media center across town, Maihesuti, the Xinjiang governor, appeared to accuse journalists of exaggerating the terrorist threat to the games.

"These terrorist groups are not as capable as some media organizations have claimed or broadcast," Maihesuti said.

Many of those labeled terrorists were merely "lawless people," he said. Human rights groups have long accused Beijing of classifying many personal disputes or criminal acts as terrorism to justify harsh oppression.

Maihesuti said the government knew of only "around three to four" Xinjiang terrorist groups, and government successes against their plots show their lack of effectiveness.

New terrorist concerns were prompted last week by videotaped threats purporting to be from an Islamic militant group claiming responsibility for explosions in four western Chinese cities in recent months, including two bus bombings authorities say killed two.

One militant, identified by the Washington-based monitoring group IntelCenter as commander Seyfullah, warned athletes and spectators, "particularly the Muslims," to stay away from the Olympics.

"Our aim is to target the most critical points related to the Olympics. We will try to attack Chinese central cities severely using the tactics that have never been employed," he said.

Chinese police have played down the threat, saying the explosions in Chinese cities the group claims were not the work of terrorists.