Tech info here....
Join Date: Jun 2008
I would say the cambelt has snapped, as if it snaps it can still make a noise when turning over, check and listen if it sounds like it is turning over quicker, if it sounds faster then id say the belt has gone.
The damage would have already been done so dont worry about turning it over again, you can get your fingers behind the cover on the top, pull it away from the cam cover and push the belt and see if it is really floppy.
If it has gone , it may also be due to the water pump seizing up and you would have damaged vavles.
If you take it to an indepenant place make sure they have the tools as it cant be done 100% without them.
Hope this helps......good luck