One in 10 web pages scrutinised by search giant Google contained malicious code that could infect a user's PC.
Researchers from the firm surveyed billions of sites, subjecting 4.5 million pages to "in-depth analysis".
About 450,000 were capable of launching so-called "drive-by downloads", sites that install malicious code, such as spyware, without a user's knowledge.
A further 700,000 pages were thought to contain code that could compromise a user's computer, the team report.
To address the problem, the researchers say the company has "started an effort to identify all web pages on the internet that could be malicious".
Jeeze, you would think their bots would be able to check for most types of mallicious code by now. They really need to do something about this. BBC News Report