Supporters, protesters greet Olympic torch's arrival in Beijing

Tens of thousands of Chinese supporters greeted the Olympic torch as it entered Beijing's Forbidden City on Wednesday after a six-continent tour dogged by pro-Tibet protesters until the very end.

As the Olympic torch made its way through Beijing, police detained two British and two American protesters who breached tight security near Beijing National Stadium and unfurled a banner calling for a free Tibet.

Two of the demonstrators scaled a lamp post to display the banner in front of the now iconic stadium known as "Bird's Nest," where in just two days the world's athletes and thousands of spectators will gather for the Summer Games' opening ceremonies.

Reached by telephone by the BBC, one of the climbers, who identified himself as Iain Thom, said he was a longtime pro-Tibetan activist and was protesting the Olympic "whitewashing" of China's human rights record in Tibet.

The protesters came down peacefully and were taken into custody peacefully after about an hour, said Lhadon Tethong, spokeswoman for Students for a Free Tibet, the group that organized the protest.

"We have not had any contact with them because their phones are off," Tethong said.

But the torch received an enthusiastic greeting from large crowds of cheering supporters in China's capital, with professional basketball star Yao Ming, perhaps China's most famous athlete, carrying the flame into Tiananmen Square.

Balancing a seven-year-old boy on his head and tiny Chinese flags pasted to his sweating cheeks, truck driver Liu Zheng chanted, "Long live China, long live the Communist Party, long live peace!" as the torch passed by him.

"I hope everybody will share our passion for these Games," he said.

Wu Xiu Rong, a 68-year-old retiree who is volunteering in Beijing to help people who need directions, said all of China wants this Olympics to be the best ever.

She told CBC News that the Beijing Games aren't just about sports, but also about showing the world China is no longer a backward nation of starving peasants.

"You people used to call us 'the sick man of Asia,'" she said. "We've changed."

Olympics 'moment of great pride' for China: Dalai Lama

The protest came as Chinese authorities are on high alert after an attack in the northwestern province of Xinjiang that killed 16 police officers and wounded 16 others. The attack is believed to have been carried out by Muslim Uyghur separatists.

Protests against China's human rights record and its policy in Tibet greeted the Olympic flame relay in London, Paris and other cities earlier this year.

In a statement on Wednesday, the Dalai Lama, Tibet's spiritual leader, reiterated his support for the Beijing Olympics, saying they are "a moment of great pride to the 1.3 billion Chinese people."

"These Games should contribute to promoting the Olympic spirit of friendship, openness and peace," he said.

Tethong said she understands that some argue the Games should be about sport, not politics.

But she accused China of "backsliding" on human rights since it was awarded the Games, and said the continued repression in Tibet following a violent crackdown on dissents in March is "the worst we've seen in decades."

"In the years since China won the bid, and even in recent days, they've used the Games as a pretext to crack down on people, and not just Tibetans, but the Chinese themselves," Tethong told CBC News in an interview from Bangkok, Thailand.

The torch arrived back in the capital late Tuesday, after an emotional run in Sichuan province, the site of China's deadly May 12 earthquake, which killed almost 70,000 people and left about five million homeless.

The relay will continue Thursday and Friday, before ending its journey at the Bird's Nest stadium for the opening ceremonies.