Trying to remove git repo on ubuntu guest

I am trying to remove whole git repository from my local machine, but git prohibits to delete several files.

I've tried:

1. rm -r folder
2. It asked me do I want to delete some write-protected files? I've asked y.

3. Following message appeared:

   rm: cannot remove ‘.git/objects/08/fa4fcd8413b84a1605e1c4866cb2493daf4c4e’: Operation not permitted
   rm: cannot remove ‘.git/objects/96/de4fe9aa42239290cae341427649f2afbdab16’: Operation not permitted
   rm: cannot remove ‘.git/objects/fd/ed37600b5fe66e1a0d0e4355b387e56ca2638e’: Operation not permitted
   rm: cannot remove ‘.git/objects/pack/pack-cb277ab3b4a3510209a9784a76760e6281da5218.idx’: Operation not permitted
   rm: cannot remove ‘.git/objects/pack/pack-cb277ab3b4a3510209a9784a76760e6281da5218.pack’: Operation not permitted
   

The ls command showed that all local files were deleted. Then I tried sudo rm -r .git from that folder - same result.

Help me please delete that folder.

So I figured it out. The problem was that on my host machine (windows 7 x64) this folder was allowed to read only. I disabled it, and removed it from the host machine. Sorry for not saying that it was mounted, and thanks for all replies : )