ANCIENT OLYMPIA, Greece (AFP) - Protests against China's human rights record and crackdown in Tibet disrupted ceremonies on Monday to light the Olympic flame for the Beijing Games.

Three men from a media rights group breached tight security around Ancient Olympia to unfurl a flag demanding a boycott of the Olympics. Later 10 Tibetan activists staged a protest in the town's main street before they were detained or chased by police.

International Olympic Committee president Jacques Rogge said there was no "momentum" for a boycott of the Games which start in the Chinese capital on August 8.

"I think it's always sad when there are protests, but they were not violent and that's the most important thing," Rogge told reporters.

The three members of the Reporters Sans Frontieres (Reports Without Borders -- RSF) group, staged their first protest as the chief Beijing Olympics organiser, Liu Qi, who is also the capital's municipal communist party chief, made a speech.

One man unfurled a flag declaring "Boycott the country that tramples on human rights." Another tried to grab the microphone from Liu and shouted "Freedom! Freedom!" in front of Rogge and other officials.

Security officers quickly dragged all three away. The RSF secretary general Robert Menard and two other activists were taken to the nearby city of Pyrgos, where they were later charged with an "offensive act."

"Our trial has been set for May 29. We will be there to denounce again the corruption of Olympianism" at the Beijing Games, Menard told AFP on his release.

The charge against them of "an offensive act is not the same as a provocation," he said, and is subject to a maximum one year prison term and/or a fine.

"We will continue similar protests until August 8," Menard had told AFP earlier by telephone from a Pyrgos police station.

"We have nothing against the Olympic Games or the athletes. We want to draw attention to the fact that China is the world's biggest prison," added Menard, who was presented with the Legion of Honour, France's top civilian award, by President Nicolas Sarkozy, on Sunday.

Greek police had imposed heavy security, including armed police watching down on the site from nearby hills. Greek state television cut its live broadcast away from the protesters. China's state broadcaster also quickly changed and did not mention the demonstrators.

Actors in ancient Greek costume carried out the traditional ceremony unhindered, using a parabolic mirror to focus the sun's rays and kindle a flame on the torch.

As dignitaries dispersed, about 10 Tibetan activists, covered in red paint, marched out of an Olympia hotel and lay down in the town's central street, shouting slogans against China's rule in Tibet.

Police detained at least two of the activists and chased the others.

A Tibetan woman involved in the street protest, who is a Swiss passport holder, was also held in Pyrgos, but a number of other people were released, police said.

They included a German companion of the Tibetan girl, a Japanese man found carrying a small knife at the entrance of the Olympia ceremony site, a Greek photographer and a Tibetan student protest leader who was part of an anti-Chinese protest at Olympia on March 10, police said.

Speaking before the ceremony, Rogge said "the major political leaders don't want a boycott." He added: "There is no momentum for a boycott."

"Bush doesn't want a boycott, Sarkozy doesn't want a boycott, Brown doesn't want a boycott," Rogge said, referring to US President George W. Bush, President Nicolas Sarkozy of France and British Prime Minister Gordon Brown.

But he acknowledged that the torch relay across 20 countries - and Mount Everest and Tibet - might be hijacked. "Of course it's a concern," he said.

In his speech at the ceremony, Rogge said the Beijing Games should be an opportunity for China and the world "to learn, discover and respect each other."

A crackdown on anti-Chinese protests in Tibet, which exiled Tibetans say has left at least 130 dead, has overshadowed the build-up to the Games.

Various rights groups have drawn up plans aiming to galvanise opposition to China's record on Tibet, Darfur, human rights, religious freedom and other issues in the run-up to the Beijing Games.

The torch's journey to Beijing is the longest ever, lasting 130 days and covering 137,000 kilometres (85,000 miles) worldwide. Most of it will be on Chinese soil.

Aside from Athens, the flame will only stop in London and Paris among European capitals. It will stop in San Francisco and Buenos Aires in the Americas and just Dar es Salaam in Africa.

Upon arrival in Beijing, one flame will be separated from the torch and kept in a special lantern to be taken to the summit of Mount Everest.