BEIJING (Reuters) – At least eight American blogger-activists and several other foreigners have been detained in Beijing as the government intensifies a crackdown on pro-Tibetan protests in the home stretch of the Olympics, rights groups said on Wednesday.

Students for a Free Tibet earlier said authorities detained five self-styled “citizen journalists” who were in Beijing to promote Tibetan freedom on Tuesday. The New York-based group said activist-artist James Powderly had also been nabbed.

Later on Wednesday, the group said four more protesters, including two Americans and a British national, were also detained after unfurling a Tibetan flag outside the National Stadium, or “Bird’s Nest.”

The Beijing Olympics have not been dogged by the widespread demonstrations that authorities had feared. Several protesters advocating for Tibet independence have nonetheless managed to breach tight security, in one case hanging a “Free Tibet” banner outside the headquarters of the state broadcaster.

China is particularly sensitive to criticism of its rule in Tibet, the far-western region Communist troops entered in 1950.

“In relation to foreigners holding demonstrations in Beijing in support of Tibet independence, competent authorities have the right to handle these things according to law,” Foreign Ministry spokesman Qin Gang told a news conference on Wednesday.

“I’d also like to emphasize that in China, activities that support Tibet independence will be strongly condemned by the Chinese people and will not be welcomed.”