Human rights activists accused Vietnam of infringing freedom of religion after a court handed jail sentences this week to six ethnically Khmer Buddhist monks and three religious activists.
A court in the southern province of Long An condemned the men to prison terms between two and six years after finding them guilty of "abusing democratic freedoms to infringe upon state interests" and illegally detaining people, according to a police statement.
Among them, Khmer Krom Buddhist monk Thach Chanh Da Ra was given the longest, six-year prison term during a trial on Tuesday, Vietnam's Ministry of Public Security said in a statement.
Asia Human Rights and Labour Advocates (AHRLA) said late on Wednesday the sentences against the monks were "outrageous and unacceptable."
The police said Thach Chanh Da Ra instructed his followers to illegally detain and attack local authorities when they tried to search the temple where he resides.
It was not immediately clear why the temple was searched and the motives for the monks' resistance.
Reuters was not immediately able to contact the monks' lawyers.
"What was really on trial was the Khmer Krom people's right to practice their religion, language and culture without interference from Vietnam's ruling Communist party," said AHRLA director Phil Robertson, referring to the Khmer ethnic group living in Vietnam's Mekong Delta, most of whom are Buddhists.
Vietnam's foreign ministry didn't immediately respond to a request for comment.
He said the sentences showed the government was intolerant of the freedom of religion and belief outside strictly controlled official structures.
"The international community should publicly condemn these blatant rights violations and demand that these monks and activists be immediately and unconditionally released," Robertson said.
The U.S. Department of State included restrictions of religious freedom among a long list of "significant human rights issues" in a 2023 report about Communist-run Vietnam.