Unknown hackers have shut down the prize-winning online publication The Irrawaddy, which reports on affairs inside Burma from the northern Thai city of Chiang Mai, the publication's editor said Monday.

The cyber-attack occurred on the second anniversary of the so-called Saffron Revolution, when thousands of Buddhist monks took to the streets in protest of the military junta that has ruled the country for decades. At least 31 people were killed in the 2008 incident, according to the United Nations, and scores of dissidents, including Buddhist monks, labor and community activists were jailed for up to 65 years after the military cracked down ruthlessly on the biggest challenge to the junta since it seized power in 1998 after refusing to ratify an election that the opposition won overwhelmingly.

The junta has been preparing for months for its so-called "Road Map to Democracy," an election that has been branded a sham by human rights organizations and a flock of governments. The election, to be held in November, has denied all credible opposition leaders the ability to run for office and seems guaranteed to perpetuate the military in command of the country. The junta is believed to not want any interference with the electoral process, including through the Internet, which has rendered Burma's attempts to wall out information useless.

Aung Zaw and other exiled Burmese journalists established The Irrawaddy in 1993 as an independent, nonprofit media organization to provide in-depth news and information on Burma and Southeast Asia. It isn't affiliated with any political organization or government. Its intrepid reporters dash in and out of Internet cafes just long enough to deliver reports on the preparations for the election, or how they are being blocked. On Aug. 8, Asia Sentinel reported on the way the independent journalists are able to elude authorities in a bid to get the news out on what is going on in the country.

For instance, Irrawaddy reported on September 8, in a story carried on Asia Sentinel, that the millions of voters in rural areas see little advantage in voting, have no idea about political developments in the country or the political parties that will be involved in it.

"This is second largest attack since September 2008, exactly two years after the Saffron Revolution," said Aung Zaw, the Irrawaddy's editor, in an email. "This is far more serious than the past ones." The attack was a so-called DDoS, or "distributed denial of service" attack, which consists of flooding the target website with so many requests that it can't respond to traffic, or is forced to respond so slowly that it become ineffective. They either force the target site's computer to reset or block its resources so that it can no longer communicate.

The hackers, Aung Zaw said, "attacked our on-line store a few weeks ago and left a warning message saying that they were coming back to us and so they did. But who are they? Cyber criminals who are hired by the regime or the regime's paid mercenary cyber hackers? I think we all know the usual suspects." The hackers also attacked Aung Zaw's own personal website, he said.

"Burma's military junta has so successfully suppressed the media that Internet sites based outside the country are one of the few remaining sources of reliable news for Burmese people," Aung Zaw wrote in 2008 in the Wall Street Journal/Asia after the first attack. "Now it appears not even those sites are safe. Shortly before yesterday's anniversary of the 1988 pro-democracy uprising and last year's Buddhist-monk-led Saffron Revolution, the Web sites of my newspaper, The Irrawaddy, and other Burmese news portals came under cyber attack. I am not alone in believing that the junta is behind the attack, just as it was behind the shutdown of Internet access in Burma during last year's uprising.

"On Tuesday, we received reports from our stringers and regular readers that Internet connections in Burma were running slowly. The number of these reports suggested a concerted effort to prevent information from going in or out of the country in the run-up to yesterday's important anniversary. The next day, our colleagues and subscribers in the United States, Japan and Malaysia notified our Thailand-based office that they were unable to access our Web site, www.irrawaddy.org.

"A few hours later, inet, the largest Internet host server in Thailand and the primary host of our site, confirmed our site had been under a "distributed denial of service" attack since 5 p.m. that day. Someone had managed to freeze our site by bombarding us with so much traffic that our server couldn't cope. Inet finally decided to shut down our server."

In lieu of the Irrawaddy site, the organization put up the following notice:

"This blog is a temporary mirror site of www.irrawaddy.org. It has been set up so that we can continue to keep readers updated with our online content. The Irrawaddy's English and Burmese websites at www.irrawaddy.org and www.irrawaddy.org/bur have been under DDoS attack since 12:30 a.m. on Monday. Our mirror site at www.irrawaddymedia.com also came under the same attack. The attacks coincide with the third anniversary of the "Saffron Revolution," the monk-led protest in Burma. The first major attack was in September 2008, on the first anniversary."