Misterious Navigation block shows up for anonymous users

I installed the "Recent Blocks" module and disabled it, now I get this strange block for unregisterd users that says "Navigation" and gives them a link to Recent posts. I can not seee this block under "Blocks" How do I get rid of it?

here is the link to my site:

http://revista-andea.com/

It is under the login block.

Thank you!