HANOI – Vietnam has detained four people who local news reports said colluded with prominent lawyer Le Cong Dinh, arrested last weekend on charges of spreading propaganda against the state.

The four had helped plot the toppling of the Communist-run state with the intent of replacing it with a multi-party system, the online news portal VNExpress reported Friday. It named two of the detained as Tran Huynh Duy Thuc and Le Thang Long.

State media said Dinh published articles on the Internet that intentionally distorted Vietnam's socio-economic policies and libeled key leaders.

The 40-year-old lawyer was also accused of damaging and distorting Vietnamese law and the constitution in his defense of high-profile democracy activists.

He could face up to 20 years in prison.

Dinh's arrest has sparked criticism from abroad.

A U.S. State Department spokesman said the United States was deeply concerned, and New York-based Human Rights Watch called for Dinh's immediate release, saying the arrest was part of a campaign by the state against rights and democracy activists.

Amnesty International labeled Dinh's arrest another indication of Vietnam's determination to stifle freedom of expression, and silence anyone who criticizes the government or holds different views.

The International Bar Association's Human Rights Institute wrote a letter to Vietnamese Prime Minister Nguyen Tan Dung saying it was concerned the arrest contravened the Vietnamese constitution's guarantee of free speech.

In the state's defense, Foreign Ministry spokesman Le Dung said in a statement Dinh's arrest conformed with relevant procedures and Vietnam consistently ensured freedom of speech and expression.

Several state-run newspapers said Friday that Dinh had confessed, and he was shown on state TV Thursday night reading a statement.

The Communist Party newspaper Nhan Dan printed images of handwritten testimony it said Dinh wrote to security authorities on June 17, four days after his arrest, detailing his activities.

I think the above actions of mine violated Vietnamese law. I feel very repentant for my wrongdoings. I look forward to the state's consideration so that I may have clemency, it said.

Media reports said Dinh attended a non-violent struggle course in the Thai beach resort of Pattaya earlier this year and became a member of the U.S.-based Vietnam Democratic Party.

In 2007, Dinh defended two other prominent human rights lawyers, Nguyen Van Dai and Le Thi Cong Nhan, who were jailed on similar charges of spreading propaganda against the state.

Dinh also worked with Nguyen Quoc Quan, a U.S. citizen of Vietnamese origin who had planned to distribute pro-democracy literature.

The International Bar Association's Human Rights Institute said Dinh had more recently been involved in a complaint about a controversial bauxite mining project in Vietnam's Central Highlands that has sparked a chorus of dissent.

(Editing by Jerry Norton)

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