Beijing - Activists in Tibet began a four-year campaign yesterday to spoil China's hosting of the 2008 Olympics.

Two men belonging to a network of more than 100 groups supporting the Dalai Lama staged a protest in Beijing. They were interrogated by police after unfurling a banner on a bridge near the Olympic park, which is under construction, calling for the Beijing Games to be boycotted.

The groups aim to make international opposition to Beijing's claim to Tibet an issue inside China for the first time since the People's Liberation Army marched on the remote mountain plateau more than 50years ago, leading to the Dalai Lama's flight into exile.

Activists are planning mass protests in Beijing before and during the 2008 Olympics. They count on the support of hundreds of foreign athletes who will be encouraged to raise the issue of Tibet in live television interviews and to display the Tibetan flag and images of the Dalai Lama, prohibited under Chinese law.

A Beijing-based diplomat said: "When China won the right to host the Olympics in 2001, party leaders celebrated it as a propaganda coup. But it's a double edged sword. Attention may be drawn to controversial subjects as much as to China's recent reforms."

With the end of the 2004 Games in Athens on Sunday, Beijing has become the focus of international attention.

"While China celebrates receiving the Olympic flag, hundreds of Tibetan political prisoners languish in prison and the Tibetan people live without basic human rights," Alison Reynolds, the director of the British-based Free Tibet Campaign, said in Beijing. "As long as the Chinese Government occupies Tibet, it does not deserve the honour of hosting a prestigious international event."

Meanwhile, Beijing's official media celebrated the 2004 Olympics as a great success for China, which won 32 gold medals, and saw it as a good omen for 2008.

"The China miracle, Asia and Africa rise up," the Beijing Times said. Workers representing the international proletariat are shown with late Communist Party chairman Mao Zedong's Little Red Book in their pockets, the interlocking Olympic rings clutched to their chests.