London: Security experts from Microsoft and anti-virus specialists Symantec have shut down a botnet that was believed to be illegally raking in over one million dollars a year.
Teams working with Microsoft and Symantec raided several data centres in the US.
The firms said computers infected by the Bamital botnet were being used for identify theft.
Experts said that affected users, of which there were thousands, were offered free tools to help clean up the infected machines, the BBC reports.
By the time the botnet was shut down, Microsoft and Symantec believed anything between 300,000 and one million machines may have been actively infected.
In order to combat the botnet, Microsoft and Symantec temporarily disabled infected users` ability to search the web, instead presenting them with a warning screen explaining the problem and how to solve it.