The official announcement of Prince William's engagement to Kate Middleton happened less than 24 hours ago, but that hasn't stopped hackers exploiting web users searching the net for the latest news about the happy couple.

According to security firm Websense, poisoned search results have already started appearing in Google and other search engines. The search results lead to malicious web pages that infect a user's PC with malware when they navigate to the pages.

According to Websense's 2010 Threat Report, more than one in five (22.4 percent) of all searches for current news lead to malicious search results.

"Prince William's engagement is the latest example of a hot media topic that is being used to manipulate search engine results to make malicious links appear higher than legitimate links," said Carl Leonard, senior manager, Websense Security Labs.

 It is an increasingly popular method of attack for cybercriminals, and one that shows they are using ever more sophisticated techniques."

 Leonard said threats on the internet are changing rapidly and security needs to be kept up to date to match threats.

He warned consumers and businesses not to rely on security tools bought two or three years ago, and to remain vigilant, making sure only reputable sites are visited when looking for news for example rather than just conducting random searches.

Security firm Sunbelt Software said that within minutes of the engagement being made public, it detected a poisoned link that appeared in results when 'images of Kate Middleton' was searched for on Google. The link displays the image but then redirects the user to, where a Trojan is downloaded on to their PC.

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