Code and screenshots of Microsoft’s forthcoming Internet Explorer 7 browser have been leaked onto the web.
The public appearance of raw code and screenshots on developer and Windows enthusiast sites comes as Microsoft prepares to launch the first public beta of the more secure browser later this quarter.
Beta 2 of the browser, which has been the subject of leaks in recent days, will follow a more limited beta which started at the end of last year.
Internet Explorer 7 is being designed to be more secure against the current IE6 and to offer greater user functionality.
Tabbed browsing and anti-phishing features are designed to allow IE to rival the features already offered by the likes of the Firefox open-source browser.
Microsoft usually spreads developer news on IE7 through an official blog. It is not known where the unofficial code and screenshots originated.