Google+ is being investigated by the US's Federal Trade Commission (FTC) after changes to its search tool that prioritise Google+ results, according to reports.

Although the FTC is already looking into Google for potential antitrust activities (for monopolising the internet and that kind of thing), Reuters' source says the investigation has been expanded to take in the new Search Plus Your World feature.

If true, Twitter will no doubt welcome the news after slamming Google for 'warping' search results by showing results from users' Google+ accounts in web searches.

Plus one that, Google

The new search functions prompted a war of words between the two companies, with Twitter presumably concerned that Google is using its search clout to push its own social network at the expense of other independent sites.

Despite Bloomberg reporting the same news from two separate sources as well as Reuters' information, the extended investigation is not a given - Google has already denied that the FTC has asked it about Google+ and the FTC is staying tight-lipped about its activities.

Reuters' source reckons that the FTC's full investigation, which began in June 2011, is around half way through.

From Reuters