HANOI (Reuters) - A Vietnamese court on Thursday upheld a 10-year jail sentence for a prominent blogger convicted of publishing propaganda against the state, her lawyer said, the latest move in a crackdown on critics of the one-party state.

Despite sweeping economic reform and increasing openness towards social change, including gay, lesbian and transgender rights, Vietnam’s ruling Communist Party retains tight media censorship and does not tolerate criticism.

In recent months, it has targeted critics whose voices have been amplified by social media in a country that ranks among Facebook’s top ten, in terms of users.

Nguyen Ngoc Nhu Quynh, 37, known as “Me Nam” (Mother Mushroom), who gained prominence for blogging about environment issues and deaths in police custody, was found guilty in June for distributing what police called anti-state reports.

A court in the central city of Nha Trang upheld Quynh’s sentence, one of her lawyers said.

“This sentence is not objective and is unfair,” the lawyer, Ha Huy Son, told Reuters by telephone.

“Quynh said she is innocent and she carried out her right as a citizen.”

Vietnam’s state news agency confirmed the outcome of the appeal. The hearing was public and “in accordance with Vietnamese law”, foreign ministry spokeswoman Le Thi Thu Hang added.

Quynh’s mother said she was among those outside the court protesting against the verdict when plainclothes policemen approached and beat them.

“The police beat me repeatedly,” Nguyen Tuyet Lan, the mother, told Reuters, adding that police detained three activists.

Reuters was not able to reach police for comment.

In March 2009, Quynh spent nine days in police detention for receiving funds from Viet Tan, a California-based activist group which Vietnam calls a terrorist group, to print T-shirts with slogans against a major bauxite project, police said.

She has also spoken out against a subsidiary of Taiwan’s Formosa Plastics Corp that caused one of Vietnam’s biggest environmental disasters in April.

The European Union, whose representatives were denied access to the appeal hearing, urged that Quynh be “immediately and unconditionally released”, its Vietnam delegation said on Friday, ahead of an annual human rights session in Hanoi.

A U.S. diplomat in Vietnam said she was “deeply troubled” that Quynh’s conviction was upheld.

“The United States calls on Vietnam to release Ms Quynh and all prisoners of conscience immediately, and to allow all individuals in Vietnam to express their views freely and assemble peacefully,” Caryn McClelland, the U.S. chargé d’affaires, said in a statement.

New York-based Human Rights Watch called the hearing a farce.

“The proceedings were a farce, with the judge simply going through the motions before issuing the harsh verdict predetermined by the ruling communist party, upholding her long prison sentence,” said Phil Robertson, the group’s deputy director for Asia.