Removing an image from the server

I have gone through the recommended process of permanently deleting an image in the media library. I have also deleted the post that was associated with the image. I can confirm the image is no longer in my library – the problem is that it can still be accessed directly from my uploads folder at http://elcyclista.com/wp-content/uploads/2010/06/stelvio.jpg and I really need to remove the image – Is it possible for me to remove this image from the server? How do I stop access to this image

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