According to Comscore Media Metrix, the top 15 news sites have seen traffic rocket by more than 40%.
head of editorial development Nic Newman said traffic to the site had almost tripled and he expected it to rise further. and are believed to have experience similar levels of traffic.
Some sites are slowing down because of the amount of traffic. According to web monitoring firm Keynote Systems, the time BBC Online's pages took to download increased to 1.88 seconds during the lunchtime period from 0.47 seconds normally.
ITV News's download time slowed to an average 15.84 seconds from its usual 5.66 seconds. The Sun's website is also said to have showed signs of strain.
Internet users are also logging on to government sites in the UK and the US are also experiencing high numbers of visitors. According to Keynote, the page the UK Home Office developed to give advice about what to in the event of a terrorist attack has been taking a minute to download.
The main page of the Foreign and Commonwealth Office website was taking 90 seconds to download. Yesterday, it was warning UK citizens to leave Jordan and Kuwait.
The US Army site was taking more than 80 seconds to download at its busiest period and, for almost 30% of visitors, the site did not appear at all. The US Marine Corp site is said to have suffered similar problems.
Elsewhere around the world, text messages were flying. In Manila, one anti-US message that is doing the rounds said: "Have you heard that when the United States takes over Iraq, it will divide the country into three zones -- premium, regular and unleaded."
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