The US government, apparently aided by freelance computer hackers, chased WikiLeaks from an American commercial computer network and temporarily stopped the leak of embarrassing diplomatic documents. But within hours, the website was back online, publishing from a fortified bunker in Sweden.

The virtual chase yesterday was mirrored by a real-life pursuit as European authorities hunted for the site's fugitive founder, Julian Assange, who is wanted in Sweden on rape charges.

Undeterred, Assange continued releasing confidential government documents. Some showed how the Obama administration and Congress helped persuade Spain not to pursue charges against members of George W. Bush's administration for allowing torture of terrorism suspects.

Amazon.com Inc. prevented WikiLeaks from using the US company's computers to distribute embarrassing State Department communications and other documents, WikiLeaks said yesterday. The WikiLeaks site was inaccessible for several hours before it returned to servers owned by its previous Swedish host, Bahnhof, which are housed in a protective Cold-War era bunker. Tech blogs have compared it to a lair from a James Bond movie.

Amazon's move to evict WikiLeaks from its servers came after congressional staff called the company to inquire about its relationship with WikiLeaks, Sen. Joe Lieberman, an independent, said yesterday.

"The company's decision to cut off WikiLeaks now is the right decision and should set the standard for other companies WikiLeaks is using to distribute its illegally seized material," Lieberman said in a statement. He added that he would have further questions for Amazon about its dealings with WikiLeaks.

The White House said it was taking new steps to protect government secrets after WikiLeaks released thousands of sensitive US diplomatic cables. Officials said national security adviser Tom Donilon has appointed a senior aide to identify and develop changes needed in light of the document dump.

The White House also spurned a call from Assange for Secretary of State Hillary Rodham Clinton to step down if she had any role in directing US diplomats' spying on other foreign leaders. "Mr. Assange's suggestion is ridiculous and absurd, and why anyone would find his opinion here relevant is baffling," said spokesman Tommy Vietor, adding Clinton was doing an "extraordinary" job. The White House says US diplomats do not engage in spying.