Vietnam faced criticism Wednesday from the United States and rights groups after jailing three pro-democracy bloggers weeks ahead of the communist government's party congress.
The run-up to a leadership transition later this month is a particularly tense period for the state as candidates jostle for power behind closed doors.
In recent months, the authoritarian regime has stepped up its crackdown on dissent and has arrested numerous critics.
At a quick trial Tuesday in Ho Chi Minh City, three critics of the state who belong to the outlawed Independent Journalists Association of Vietnam (IJAV) were sentenced to jail for "making and disseminating information against" Vietnam.
High-profile writer Pham Chi Dung, 54, founding member and president of IJAV, was jailed for 15 years, while military veteran Nguyen Tuong Thuy, 69, was sentenced to 11 years.
A younger member of the group, Le Huu Minh Tuan, was also handed an 11-year term.
The United States -- which, despite war memories, has a warming relationship with Vietnam led by shared concerns on China -- said it was "disappointed" by the sentences.
"These harsh sentences are the latest in a worrisome trend of arrests and convictions aimed at Vietnamese citizens exercising rights enshrined in Vietnam's constitution," a State Department spokesperson said in Washington.
"We urge the Vietnamese government to ensure its actions are consistent with the human rights provisions of its constitution and its international obligations and commitments."
- Well-known advocates -
The imprisoned trio are well-known for calling for greater democracy in Vietnam.
Lawyer Nguyen Van Mieng told AFP they admitted writing articles "to support freedom of speech and other democratic rights", but denied spreading information against the communist regime.
According to the court's verdict cited by state-run media, the three "had regularly been in contact with regime opponents" prior to their arrests in late 2019 and mid-2020.
IJAV leader Dung had written articles for foreign media agencies with "the purpose of changing Vietnam's political system," it said.
The defendants' behaviour posed "a danger to society... causing separation in social unity and people," it added.
Amnesty International's deputy regional director, Emerlynn Gil, said the sentences showed the depths of Vietnam's censorship "even by its own deeply repressive standards."
"These journalists' only crime was daring to discuss politics and other matters of public interest," she said.
Radio Free Asia, the US government-funded broadcaster where Thuy contributed commentary, called for his immediate release.
"The harsh sentencing of Thuy and two other independent journalists is a blatant assault on basic freedoms and flies in the face of the freedom of expression enshrined in Vietnam's constitution," Radio Free Asia president Stephen Yates said.
There are more than 170 prisoners of conscience currently imprisoned in Vietnam, according to Amnesty.
In December, writer and poet Tran Duc Thach was sentenced to 12 years for his articles critical of the government posted on Facebook, nearly a decade after being released from prison for a similar offence.
The Communist Party Congress will take place from January 25 to February 2 in Hanoi.