HANOI (Reuters) - A court in Vietnam jailed a prominent dissident for nine years and gave her five years probation for spreading propaganda against the state, her lawyer said on Tuesday, in what appeared to be the Communist-ruled country’s latest crackdown on critics.

Despite sweeping reforms to its economy and growing openness to social change, including gay, lesbian and transgender rights, Vietnam’s Communist Party retains tight media censorship and does not tolerate criticism.

Blogger Tran Thi Nga was found guilty at a one-day trial in the northern province of Ha Nam, six months after being arrested for posting the offending material on the internet, lawyer Ha Huy Son said.

“This is an unfair verdict,” he said. “Nga is not guilty as stated by the court.”

The charges against Nga are “bogus”, said New York-based Human Rights Watch.

“The Vietnamese government consistently goes to extremes to silence its critics, targeting activists like Tran Thi Nga with bogus charges that carry a long prison sentence, and subjecting their families to harassment and abuse,” its deputy Asia director, Phil Robertson, said in a statement.

The United States also called on Vietnam to release Tran Thi Nga and all other prisoners of conscience, and to allow all individuals in Vietnam to express their views freely and assemble peacefully without fear of retribution.

“We have seen some positive steps on human rights in Vietnam over the past few years. However, the trend of increased arrests, convictions, and harsh sentences of peaceful activists since early 2016 is deeply troubling,” U.S. Ambassador in Vietnam Ted Osius said.

Separately, police on Monday arrested a prominent dissident they have accused of conducting activities aimed at overthrowing the government.

The arrest of Le Dinh Luong, 51, followed his “regular activities with the aim to overthrow the authority and complicate local security,” police in the central province of Nghe An said on their news website, but did not elaborate.

It was not possible to contact Luong and it was not known if he had legal representation.

Nga’s verdict and Luong’s arrest come just a month after a court jailed prominent blogger Nguyen Ngoc Nhu Quynh, known as “Me Nam”, or Mother Mushroom, for 10 years for publishing propaganda against the state.

Several dissidents and bloggers voiced support online for both Nga and Luong. With information tightly controlled by the government, some critics take to web blogs to air grievances and social media sites, including Facebook, are hugely popular.

Luong and Quynh had both spoken out against a subsidiary of Taiwan’s Formosa Plastics Corp that caused one of Vietnam’s biggest environmental disasters in April.