The Burmese government appears to have cut public internet access amid the largest protests against military rule in nearly 20 years.
It is thought the move is aimed at preventing more videos, photographs and information getting out about the military crackdown on the demonstrations.
Internet cafes have been closed and the help desk at the main internet service provider did not answer its telephones to explain why there was no access.
Ordinary people have been at the forefront in informing the world of the protests against 45 years of military rule and declining living standards in Burma, also known as Myanmar.
They have even hidden news in e-greetings cards or used the social networking site Facebook.
Networks of reporters for dissident news organisations have used the Internet to get stories and pictures out.
Correspondents who covered the last major uprising in 1988, when the army killed an estimated 3,000 people, said a communications blackout was to be expected but would not stop the information flow.
'It may very well happen. It will just be a sudden shutdown,' said British journalist Dominic Faulder who was based in Bangkok during the 1988 uprising.
But he said the authorities could not prevent all information from leaving the country: 'They're going to delay the message, but they're not going to stop it. This time, there will be more pictures and they will come out,' Mr Faulder said.
The widespread use of modern technology by protestors and dissident news networks is in stark contrast to 19 years ago, when reports of massive casualties from soldiers shooting into the crowds took days to leak out.
Dramatic footage and pictures of a Japanese photographer being shot dead and soldiers marching through the streets, have been a major factor in the current worldwide outrage and diplomatic clamour for restraint.
