Attorney General John Ashcroft in the US said on Tuesday there was no evidence a new computer worm called "Nimda" was linked to last week's attacks on the World Trade Centre and the Pentagon.
Ashcroft said the new Internet infection, which spells admin backwards, may have started as early as Monday and that it affected computers worldwide by overloading traffic on the Internet.
"There is no evidence at this time which links this infection to the terrorist attacks of last week," Ashcroft told a news briefing.
He said the latest computer worm could be "heavier" than the Code Red worm that caused an estimated US$2.4 billion in estimated clean-up costs on Internet-linked computers last month.
