URUMQI, Jan. 25 -- A Uygur teacher from Minzu University of China in Beijing formed a separatist group headed by him and undertook separatist activities under the disguise of his identity, police authorities in China's far western Xinjiang region said on Saturday night.

Ilham Tohti severely damaged the national security and social stability, the municipal public security bureau in Urumqi, capital of Xinjiang Uygur Autonomous Region, said in a statement under its microblog account on Sina Weibo, China's equivalent of Twitter.

He colluded with overseas East Turkistan separatist forces and used the Internet to advocate for "Xinjiang independence" and take advantage of the classrooms to instigate the overthrowing of government, it said.

Ilham Tohti himself launched a website and used the platform with the help of his followers to make rumors and distortions of and hype up some cases and take the chances to spread separatism, instigate ethnic hatred, advocate "Xinjiang independence" and conduct separatist activities, according to the statement.

He openly championed for "the use of violence" and "Uygurs should oppose the government as (China) once opposed the Japanese invaders" at classrooms.

He also called mobs in some terrorist attacks "heroes", and instigate the students to hate the country and government and to overthrow the government.

Ilham Tohti organized a group with the disguise of his identity, colluded with leaders of overseas East Turkistan separatist forces, and sent followers overseas to engage in separatist activities, it said.

After a meticulous investigation, police authorities have uncovered the concrete evidence behind Ilham Tohti's separatist activities.

The case is still being processed.