Three dissidents in Vietnam have been jailed for up to five years for spreading anti-Communist propaganda.
The defendants were said to be a danger to the state
They were found guilty of being members of a banned political party and having links to a Vietnamese-American activist expelled from Vietnam last year.
The authorities have recently stepped up a campaign to silence dissent, and several activists have been jailed.
An ex-prime minister, with links to the current leadership, told the BBC there should be a dialogue with dissidents.
In a rare interview, Vo Van Kiet - a reformist who was prime minister from 1991 to 1997 - said the government should not avoid "talking to those who have a different view".
And he urged the authorities "not to execute administrative measures" in their dealings with dissidents.
The three jailed activists were said to be members of the banned People's Democratic Party, which campaigns for a multi-party system of government.
Le Nguyen Sang, 48, was sentenced to five years in jail, Nguyen Bac Truyen, 39, received four years and Huynh Nguyen Dao, 39, was given three years.
They were found guilty of violating article 88, which bans disseminating information harmful to the state.
Prosecutors said they had "carried out activities that aimed to end the leadership of the Communist Party of Vietnam, demanding pluralism and a multi-party system".
The three were also accused of collaborating with Cong Thanh Do, who emigrated from Vietnam to the US in the 1980s.
Do was arrested while on holiday in Vietnam and deported last September by the authorities, who accused him of plotting to overthrow the government.
Do himself condemned the sentences, saying the three had committed no crimes.
"To advocate freedom of expression, to exercise freedom of association and to seek or exchange information by peaceful means are legal acts," he was quoted by the Associated Press as saying.
Two prominent human rights lawyers in Hanoi are expected to go on trial on Friday, also accused of defaming the state.
Another lawyer faces the same charge at a court hearing scheduled for next week in Ho Chi Minh.
A Catholic priest and rights activist was jailed in March for eight years on charges of disseminating information to undermine the state.