Ubisoft's open-world action game Watch Dogs originally received an MA15+ rating from the Australian Classification Board, but it was recently submitted and classified again and it received a higher R18+ rating, it has been revealed.

The game's original MA15+ rating, published in September 2013 before the game's delay, described Watch Dogs as having "Strong themes and violence." Watch Dogs' new R18+ rating points out that it will contain "References to sexual violence and sex scenes."

Here's how the two ratings for Watch Dogs compare.

It's unclear what Watch Dogs content specifically led to the ratings upgrade and we've reached out to Ubisoft for comment. In the United States, the game originally received an M-for-Mature rating from the Entertainment Software Rating Board (ESRB) but the rating has since vanished from the group's website. An ESRB representative is looking into the matter, they told GameSpot.

Watch Dogs launches May 27 for Xbox 360, Xbox One, PlayStation 3, PlayStation 4, and PC. The Wii U version will come sometime later. For more on Watch Dogs, be sure to check out GameSpot editor Shaun McInnis' recent extensive hands-on preview of the game from his recent trip to Ubisoft Montreal.

Thank you to GameSpot reader Luke Robson for tipping us off to the news today.