How to clear my messages off of my IPhone 4G?

I have completely deleted all of my messages, but when I go into Settings<General<Usage< and then Messages, it still says that I have 772 MB of (Saved) Messages. Where else could my phone be storing them if I deleted them! (I don't have IMessage by the way)

Added (1). I have recently updated my phone to the iOS7 also

Please post a picture. As far as i know there's no messages option the Usage section. Maybe you have it on iOS 6