...ouch.
Try cleaning it off with water and a soft lint-free cloth. If that doesn't work, give rubbing (isopropyl) alcohol a shot -- get the highest purity you can from the local drugstore. I remember someone else who had a similar thing happen, and they got the ink off with alcohol. You can also get stuff that is specifically for cleaning LCD displays from most computer/electronics stores.
If they actually scratched the front of the screen, that damage is permanent. It will look a lot better with the ink cleaned off, though.