The most prominent advocate for civil and economic rights for China’s restive Uighur minority went on trial on charges of “separatism” on Wednesday, in a regional court over 1,000 miles from his university classroom in Beijing.

Ilham Tohti was one of the Uighurs willing and able to bridge the gap with Han Chinese society, teaching economics at Minzu University in Beijing and founding a Chinese-language website, UighurOnline, which offered news on his home region, Xinjiang.

Police with riot shields blocked streets 300m from the court in Xinjiang’s capital, Urumqi, and nine European and North American diplomats had their request to attend the trial rejected. “We are here because we are concerned about the treatment of Ilham Tohti,” said Raphael Droszewski, the first secretary for political affairs at the embassy of the EU.