Dinh Dang Dinh, a 49-year-old former teacher, was found guilty of spreading anti-state propaganda during a one-day trial in central Dak Nong province, a court official told AFP on condition of anonymity.

Dinh, who is also a former army official, was charged with writing and posting anti-state documents on the internet between late 2007 and the time of his arrest in October of last year.

According to local media, he expressed his opposition to the Communist Party leadership and called for democracy and pluralism in Vietnam, while also protesting against a controversial bauxite project in the Central Highlands.

Charges of spreading anti-state propaganda and attempting to overthrow the regime are routinely laid against dissidents in a country where the Communist Party forbids political debate.

"Vietnam's systematic silencing of critics by locking them behind bars only shows their intolerance for free speech that challenges government policies and priorities, and raises concerns about Vietnam's intentions towards free expression over the internet," Phil Robertson, Asia deputy director at New York-based Human Rights Watch, said in a statement criticising Dinh's trial.

"In 2012 alone, Vietnam has used this rights-violating article 88 to convict at least 10 peaceful activists and send them to serve long sentences in prison, and at least seven other bloggers and activists are currently charged and awaiting trial on the same article," he added.

Agence France Presse - August 9, 2012