In China's pre-Olympics crackdown on dissent two communities have received considerable global attention – the Tibetans and the Muslim Uighurs of Xinjiang.
Inner Mongolians, largely out of the eye of media and without attracting as much international publicity.
"Recently the authorities have been getting increasingly paranoid," Enhebatu Togochog of the New York-based Southern Mongolian Human Rights Information Centre said.
"Many Mongols travelling to Beijing have been treated as criminal suspects and are not allowed to stay in hotels in Beijing."
In March, police arrested Naranbilig, who had campaigned against Han Chinese migration to Inner Mongolia, and placed him under house arrest, Togochog said. Two weeks prior to that another dissident, Tsebegjab, was also put under house arrest.
Unlike the Tibetans, whose spiritual leader the Dalai Lama won a Nobel Peace prize for his work to promote his people's cause, and Rebiya Kadeer, the so-called "mother of the Uighur people", China's Mongolians have no such champion.
Decades of migration by the dominant Han have made Chinese Mongolians a minority in their own land, officially comprising less than 20 per cent of the almost 24 million population of Inner Mongolia.
China's treatment of its ethnic minorities has leapt into the limelight following anti-Chinese violence in Tibet in March and the pro-Tibet protests that have dogged the international leg of the Beijing Olympic torch relay.
Information for this report was provided by Reuters