Five major movie studios are suing two website owners over advertising copyrighted material over Google' s online advertising service.

According to US Today, 20th Century Fox, NBC Universal, Paramount, Sony and Warner Bros are claiming the two site owners used the Google Ads service to promote trade in illegally copied material. Exact details as to how the ad service was used and the websites in question are unclear at this time.

Google Ads is an automated service which allocates adverts to websites that are relevant to the user's comments and the site's content.

In a response to the Wall Street Journal , Google said "We prohibit advertisers from using our advertising program to promote the sale of copyright infringing materials".

Google has come under fire before for its video-hosting service YouTube 's unauthorised hosting of copyrighted material. But this is the first time the parent company has been accused directly of aiding the promotion of such material.

Despite pressure from other studios and Google's willingness to remove copyrighted clips, YouTube continues to illegally host copyrighted video clips posted by the site's users.