BEIJING -- A life sentence given to a moderate Chinese scholar on Tuesday shows the ruling Communist Party is cutting off dialogue on ethnic tensions and could backfire by radicalizing minorities, scholars and analysts said.

A court found economics professor Ilham Tohti, an ethnic Uighur Muslim, guilty of separatism and sentenced him to life in prison. It was the most severe penalty in a decade for illegal political speech in China and eclipsed the 11-year jail sentence given Nobel Peace Prize laureate Liu Xiaobo on subversion charges.

"Ilham Tohti's situation gives scholars like me who ... work on the issue great concern about our safety and academic freedom," a scholar said after Tuesday's sentencing, requesting anonymity because of fear of punishment from authorities.

Ilham Tohti is seen as a moderate voice with ties to both ethnic Uighurs and the Han Chinese majority. A Communist Party member and professor at Beijing's Minzu University, he ran the website Uighur Online that highlighted issues affecting the ethnic group.

The sentence of life imprisonment "is a very disturbing message, as the door to dialogue is closed because this scholar promoted dialogue between the Uighurs and the Chinese intellectuals," said Willy Lam, a political analyst at the City University of Hong Kong. "Beijing's message is that they do not look to dialogue with the Uighurs but suppression."

China says it faces grave terror threats, particularly in Xinjiang, the ancestral home of Uighurs. Riots in 2009 in the regional capital of Urumqi killed nearly 200 people, according to the government, and violence over the past year and a half has left more than 300 people dead, nearly half shot by police in a strike-hard campaign by the government to fight what it calls terrorist cells.

Beijing has blamed the unrest on foreign-influenced terrorists seeking a separate state. But many Muslim Uighurs bristle under Beijing's heavy-handed restrictions on their religious life and resent the influx of the Han majority into their homeland.

For years, Ilham Tohti has been speaking openly about the problems in his home region. "At present in Xinjiang, the exclusion of and discrimination against Uighurs is quite systematic, with the government leading the way," he said in an interview with Voice of America last year, following a deadly attack involving Uighurs in the heart of Beijing.

Prosecutors said Ilham Tohti was the ringleader of "a criminal gang seeking to split the country" and "caused severe harm to national security and social stability." His lawyers said the scholar's remarks -- on the Internet, in his classrooms or with foreign media -- did not advocate separatism and instead sought to resolve the region's ethnic tensions.

James Leibold, a scholar of ethnic policies at La Trobe University of Melbourne, said Ilham Tohti "made a positive, moderate, and courageous contribution to the ongoing discussion on China's ethnic policy" and his life sentence is a "real tragedy."

"The sentencing will clearly have a chilling effect on other minority scholars, especially those within the Uighur and Tibetan communities, whose voices and opinions are clearly crucial to fixing some of the problems with China's ethnic policies and creating an environment more conducive to interethnic harmony," Leibold said.

The verdict drew international condemnation.

The European Union called the life sentence "completely unjustified," and Amnesty International said the decision was "shameful" and "an affront to justice."

Nur Bekri, chairman of the Xinjiang regional government, has defended the Communist Party's ethnic policies, calling them earlier this year "the best in the world."

"Some people are always pointing their fingers at China's ethnic policy. They must have ulterior motives," he said.

When Ilham Tohti was arrested in January along with seven of his students, the Global Times newspaper, published by the Communist Party, suggested in an editorial why he was targeted. To isolate terrorist forces, it said, China must not only "strike against front-line terrorists" but also "clean up the opinion front that supports terrorism."

Yet, Beijing is adjusting its policies. For the first time in four years, it held a high-level conference to discuss the situation in Xinjiang in May. The leadership reaffirmed counter-terrorism as its top priority but also promised to improve the life of Uighurs, including providing 12 years of free education to all young people in southern Xinjiang, where most Uighurs live, and guaranteeing employment for at least one member of each household. Only nine years of free education are provided in most places in China.

But Lam, the Hong Kong professor, said Tuesday's sentencing shows the Chinese leadership has grown "paranoid."

"Policies in Xinjiang have been a failure," Lam said. President Xi Jinping "is using the pretext of national security to rule with an iron fist against dissidents."

Such heavy-handedness could exacerbate tensions, said Dilxat Raxit, spokesman for the rights group World Uyghurs Congress.

"The tragedy of Ilham is that it shows it is impossible to solve issues through peaceful methods," he said in a statement. "I am worried that more people would opt for other means of resistance and cause further chaos when they cannot affect changes and live with dignity through constructive suggestions."