Deleting Media

Hi all,

Hope you can help here.

I am trying to free up some space on my site. We have lots of images that we no longer need. I am removing them from the Media Library successfully, but they still stay in the files in my disk space.

Is there anyway to remove them from here too? Or do I need to go in here and do this seperately? I have read about having WPML plugin may affect this, but I do not use this plugin.

Thanks