(Adds attack on Web site)

YANGON, Sept 29 (Reuters) - Internet access was restored briefly in military-ruled Myanmar on Saturday, a day after a Web blackout believed to have been imposed to stop reports and pictures of a major crackdown reaching the outside world.

Internet users inside the former Burma were able to see domestic Web pages as well as send e-mails outside the country for a couple of hours before connections failed again.

Pictures and video footage relayed by citizen reporters have played a major role in fuelling international revulsion at the crackdown on mass protests against 45 years of military rule and deepening economic hardship.

State media say 10 people have been killed, although world leaders, including British Prime Minister Gordon Brown, say the figure is likely to be far higher.

The widespread use of modern technology by protesters 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.

But the generals appear to be getting more sophisticated in cracking down on dissent too.

Unknown hackers bombarded the Web site of the Thailand-based Irrawaddy Magazine, a leading window into the secretive country run by exiles and funded by foreign donors, with viruses this week and shut down its main server.

"We are under attack and we are trying to save our archives and data," Irrawaddy spokesman Kyaw Zwa Moe said of the cyber onslaught which began on Thursday.

The site, www.irrawaddy.org, received 22 million hits in the two weeks before it was knocked out, he said.

The magazine has continued to published photos and protest updates on a temporary site, www.irrawaddymedia.org. (Additional reporting by Darren Schuettler in BANGKOK)

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