Few freedoms: the report says Burma remains heavily restricted
An annual survey of media freedom has reported a mixed picture in East Asia - with some losses and some gains.
The US-based Freedom House organisation says China tightened some restrictions in 2007, but also tolerated more investigative journalism into cases of official corruption.
The report noted gains last year in Thailand and Malaysia, but said Vietnam and Laos continue to fare poorly.
It ranked North Korea as the world's most restricted media environment.
Freedom House reported that China made some progress in 2007 in allowing investigative journalists to carry out their work - in cases including corruption and enforced child labour.
But it said these gains were offset by "an elaborate web of regulations and laws", which allowed the tightening of media control and internet restrictions in China.
Freedom House said the Burmese media environment remained among the most tightly restricted in the world during 2007, with conditions worsening in August and September due to the crackdown on pro-democracy demonstrations.
As many as 15 journalists were detained during the unrest.
The report said Vietnam had reversed some of the gains in press freedom that had been made in 2006, with a crackdown on dissident writers.
It said the country's fledgling community of online pro-democracy writers was targeted by the government - with six cyber-dissidents imprisoned within one week in May.
Freedom House says press freedom has declined in the world overall.
Finland and Iceland are described as the world's freest media environments.