Updated

China has banned an outspoken writer and government critic from leaving the country to attend a literary festival in Australia, and warned him not to publish any of his controversial works overseas, event organizers said Monday.

Liao Yiwu, who the Chinese government has repeatedly barred from traveling abroad, was told he could not attend the Sydney event for security reasons, said the Sydney Writers' Festival's artistic director, Chip Rolley.

Liao had been scheduled to speak at a festival forum about China's rising power and human rights record. He was also slated to recite some of his poetry and discuss his work "The Corpse Walker," a series of interviews with people living in the margins of Chinese society.

Liao's writings, which often focus on China's lower class, are mostly banned in China, but are published in Western nations.

"Our primary concern is for Liao Yiwu, who has been denied the fundamental right to express his views freely," Rolley said in a statement. "We are astonished by the Chinese government's additional demand that he not publish his works internationally."

The Sichuan-based author's whereabouts in China were not immediately known Monday. Calls to police and Communist Party offices in Chengdu, Sichuan province's capital, either rang unanswered Monday or officials said they did not know about the case.

Liao first came under government scrutiny after publicly mourning those killed when the military crushed pro-democracy protests in Tiananmen Square in 1989. Recordings he made of himself wailing and reading his poem about the deaths, "Massacre," became popular and he was sent to prison for four years.

Michael Heyward, managing director of Text Publishing, publishers of "The Corpse Walker," said he was deeply disappointed in China's decision.