A former Vietnamese journalist who used the internet to criticise the government has been jailed for seven years, court officials said.
Nguyen Vu Binh, 35, was found guilty on espionage charges in a trial that lasted less than three hours.
He was arrested in September 2002 after he wrote articles criticising a border agreement between China and Vietnam.
Human rights groups have condemned the trial, which foreign journalists and diplomats were barred from attending.
The trial began soon after 0800 local time (0100 GMT) in the Hanoi People's Court.
Mr Binh worked for almost 10 years on the Communist Party's official journal before resigning in 2001.
He went on to write several articles published on the internet which called for political reform in Vietnam.
He also clashed with the authorities when he tried to set up an opposition party.
The China-Vietnam land pact he criticised was called Some Thoughts on the China-Vietnam Border Agreement.
The agreement, signed in December 1999 more than 20 years after China and Vietnam fought a bloody border war, has been roundly criticised by many Vietnamese intellectuals who accuse Hanoi of conceding too much to its more powerful neighbour.
Despite Vietnam's constitutional guarantees of a free press, in reality dissidents take considerable risks if they speak out.