Economist Ilham Tohti speaks to students at the Central Nationalities University in Beijing on Dec. 1, 2009. (Elizabeth Dalziel/AP)

China’s most prominent Uighur scholar, Ilham Tohti, denied charges of separatism and inciting ethnic hatred Wednesday, on the opening day of a trial that human rights groups see as a sign of Beijing’s growing repression of its mainly Muslim western region of Xinjiang.

Widely seen abroad as a model of moderation, Tohti taught economics until his arrest in January at Beijing’s prestigious Minzu University of China while also running a Web site meant to promote “discussion and exchange” of ideas between ethnic Uighurs and China’s majority Han population.

While he has been consistently critical of government policy in the Uighur homeland of Xinjiang, he insisted that he was seeking “diplomatic and peaceful ways to request justice and equality” for Uighurs, that he was opposed to separatism and that he dreamed of China becoming a “great nation of harmonious inter­ethnic coexistence.”

The Chinese Communist Party did not see it that way. Placed under increasingly tight surveillance in the months before his arrest and beaten, harassed and threatened by plainclothes police last year, he was detained in January and transferred to a detention center in Urumqi, the far-off capital of Xinjiang, where he faces trial for leading a “separatist criminal organization” that incites “ethnic hatred.”

If found guilty — and in China’s party-controlled judicial system, that is very likely — he could face between 10 years and life in prison.

Dozens of police officers, some in riot gear and others in plainclothes, guarded the courtroom and blocked off surrounding streets, Agence France-Presse reported, while diplomats from nine nations travelled to Urumqi to observe proceedings but were barred from entering the courtroom.

The trial hearing began at 10:30 a.m. Beijing time, and is expected to last two days, Li Xiaoyuan, one of Tohti’s lawyers, said on his social media account, adding that his client had denied the charges.

“Ilham Tohti is the moderate voice of criticism every government everywhere should want,” said Sophie Richardson, China director at Human Rights Watch. “While he has certainly been critical of policies, his criticism has always been constructive and has always been with a view towards increasing understanding and minimizing tensions in Xinjiang, or between the Uighur community and the central government.”

Human Rights Watch called Tohti’s prosecution a “travesty of justice”and said he faced a politicized show trial that would only serve to deepen perceptions of discrimination against Uighurs. Groups representing scholars, writers, scientists and reporters around the world have also joined in a chorus of protest at his arrest and treatment. In February, the U.S. State Department said it was “deeply concerned” about Tohti and called for his release.

“His prosecution says to the Uighur community: ‘There will be no criticism. We are not interested in your views,’ ” Richardson said. “Throwing the book at Ilham is the functional equivalent of slamming the door on any constructive discussion between Beijing and the Uighur community.”

Since arriving in Urumqi, Tohti has repeatedly been shackled, often for weeks at a time, his ankles have twice become infected and he has been denied treatment, said his lawyer, Li Fangping.

He went on a hunger strike in January for 10 days because his food was not halal — prepared according to Muslim religious traditions — and was denied food by prison authorities for a similar period after Uighur separatists carried out a deadly knife attack in the city of Kunming in March. He has lost about 40 pounds since his arrest and has eye and abdominal problems, his attorney said.

Han criminal prisoners have been transferred from other prisons to act as his cellmates and guards, reporting to authorities on his behavior and speech, and verbally abusing him, with one even starting a fight with him last month, Li said.

Tohti’s work has exposed the widespread economic discrimination against Uighurs and the suppression of the Uighur language through a program of supposedly bilingual education that had effectively become education in Mandarin. Opposed to religious extremism, he criticized a crackdown on normal religious practice in Xinjiang that he warned might make people adopt more extreme views. Perhaps above all, though, he lamented the sharp divide and distrust between Han and Uighur peoples.

The charges against him mainly relate to the now closed-down Uighur Online Web site, with hundreds of articles written by Tohti or posted by others on the site due to be presented as evidence, Li said. Seven other students or volunteers involved with the Web site have also been arrested but will be tried separately.

Elliot Sperling, an expert on Tibet at Indiana University and a friend of Tohti, said the Web site was becoming the “go-to place” for information about Xinjiang before it was closed down. Sperling said that made it a threat to the Communist Party’s determination to “control the narrative.”

“Ilham is a very moderate person, very dogged, really committed to human rights,” he said. “He knew the risks he was taking. He was very committed to it — to letting ordinary Chinese people know what Uighurs think, what Uighurs aspire to.”

Tohti, 44, was denied access to his attorneys from January to June, Li said. His family has not been allowed to see him or send him photographs of his two sons, ages 5 and 8.

“He loves his country, his own people. He never hated Han or anybody,” said his wife, Guzelnur. “We have been married for 10 years, and I know he is not like they described him to be.”

A daughter from his first marriage, Jewher, is a student at Indiana University. In a telephone interview, she said she was worried about her father but was convinced that he was doing the right thing.

Xu Yangjingjing contributed to this report.