Twitter, Facebook and LiveJournal said Monday they were continuing to fend off cyber attacks that last week derailed the popular Internet services.
"The attacks continued but we got better at dealing with them such that Twitter remains active," Twitter co-founder Biz Stone wrote in an email reply to an AFP inquiry. "Our systems are looking good and the platform is healthy."
Facebook was still seeing "botnet" driven Web page requests associated with the distributed-denial-of-service (DDoS) attacks but the volume was "insignificant," according to the California-based social-networking star.
"The attacks are continuing but LiveJournal is handling it just fine at this point," a spokesman for the blogging service told AFP.
However, there were problems accessing LiveJournal pages of a pro-Georgian blogger identified as the target of DDoS attacks intended to silence his online commentary.
Speaking to AFP in the Georgian capital Tbilisi on Saturday, the blogger said he believed Russia was behind the DDoS attacks and meant to silence his criticism of Moscow's role in last year's Georgia-Russia war.
Internet security specialists say the source of the attacks may never be determined with certainty if no one claims responsibility.
Last year's war saw Russian troops pour into Georgia following a Georgian military assault on its rebel region of South Ossetia.
After occupying swathes of territory Russian forces later withdrew into South Ossetia and Abkhazia, which Moscow recognized as independent states.
Messages from the Tbilisi-based blogger, who writes under the name "Cyxymu," were accessible at Twitter, where Monday he posted a link to a letter to Russian president Dmitry Medvedev.
Late last week, massive DDoS attacks hammered Twitter, Facebook, LiveJournal and YouTube in what Internet security specialists say was a blitz intended to prevent Cyxymu from posting his views on Russia-Georgia politics.
Twitter and Facebook have teamed with Internet powerhouse Google to investigate the attacks.
Google owns online video-sharing website YouTube and a Blogger service that were reportedly hit by cyber attacks.
Classic DDoS attacks involve legions of zombie computers, machines infected with viruses, which are commanded to simultaneously visit a website.
Such a massive onslaught of demand can overwhelm website computer servers, slowing service or knocking it offline.
An everyday chatting tool for many, Twitter has also become a weapon for dissidents to circumvent censorship in places where freedom of speech is suppressed.
(c) 2009 AFP