Briton deported amid Chinese Olympic paranoia

They refused to say why she was being deported, but last night the Chinese foreign ministry claimed that she was a member of the Tibetan Youth Congress, an exile organisation based in Dharamsala, the seat of the Dalai Lama in India. It said she had admitted to "activities against Chinese laws".

She called its statement "ridiculous", saying that though she had worked for the International Campaign for Tibet in Germany in 2005 she had not been involved in any pro-Tibet activism in the two years she has lived in China.

"I was in Beijing completely in a private capacity," she said. "I wasn't involved in any organisations."

"It's amazing the things they just make up," she added. "It's absolutely not true."

Miss Pemba, 30, was deported as the authorities, led by the Ministry for Public Security, stage a city-wide lockdown in advance of the Olympic Games.

Most recently, the authorities have placed roadblocks on the outskirts of the city, and are stopping non-Beijing registered vehicles from entering, even in some cases food lorries.

As well as refusing to renew visas for scores of foreigners in the city, the authorities have told thousands of migrant workers from other parts of the country to leave Beijing before the Games start.

Miss Pemba said it was clear that she was being expelled because as an ethnic Tibetan with British nationality she made the authorities nervous.

"On Tuesday morning when I left my flat there were people milling about," she said. "I knew something was up because there were so many of them, seven or eight. Two people were filming."

She was allowed to pack one bag, had her mobile phone taken away and was not allowed to call either the British Embassy or her parents until she was sitting on an Air China plane at Beijing's new airport.

"They said I had broken the laws of the country and I had to leave," she said. "I said, 'What have I done?' but they just said 'You should know what you have done'."

The Tibetan Youth Congress, is one of the more radical Dharamsala groups.

Some of its members have expressed frustration that the Dalai Lama's policy of non-violence and support for autonomy without independence for the province is failing to win concessions from Beijing.

But both its leaders and the Dalai Lama deny it is a terrorist organisation, as Beijing alleges.

Liu Jianchao, the foreign ministry spokesman, did not rule out a link to the Olympics.

"Dechen Pemba, a key member of the splittist organisation the Tibetan Youth Congress and a British citizen, took part in activities against the law of China during her stay, and has been deported," he said.

"Our handling of this incident is not necessarily related to China's general strengthening of security measures during the Olympic Games. Anyone who acts contrary to Chinese laws in China will be investigated at any time and handled by relevant department in accordance with laws."