Other popular search engines, including Google and Ask Jeeves, reported that Nostradamus had the biggest increase in popularity.
The 16th-century French astrologer's cryptic predictions were circulated in e-mails, suggesting he had foretold the attack which would be the beginning of World War III.
Other e-mails then circulated claiming the prediction e-mails were a hoax.
Ms Featherstone said that last week new websites emerged to cater for the disaster and new categories of websites were put on the search engine.
Nostradamus Prophecy Hoax websites had been the most popular.
The Yahoo news service also had 10 times more traffic than normal last Tuesday and 40 times more page views in the first two hours after the story broke.
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The fatal flights
Emergency telephone numbers:
United Airlines
: 0168 1800 932 8555
American Airlines
: 0168 1800 245 0999
NZ Ministry of Foreign Affairs and Trade
: 0800 872 111
US Embassy in Wellington (recorded info): 04 472 2068
Victims and survivors
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