Google has taken down ads that have been linked to efforts to steal people's banking and other information, reports the Associated Press.

The paid ads appeared in searches for the Better Business Bureau and only affected Windows XP users. Google says it took down the ads and suspended the accounts as soon as they were made aware of the issue. Searchers who clicked the link were taken to a site which automatically installed malicious code on their computers. That code then searched for personal information.

The security of Google's network has been called into question by this attack. While some more strict policies might have been put into place, it would be almost impossible for Google to vet all its advertisers because of its enormous scale.