Anode Rod Problem

I just tried to remove the anode rod from the water heater on my 1998 3023. As you can see from the photos (sorry for the poor quality), the rod broke off right at the end of the threads. I can see the stub of the wire which is surrounded by some kind of whitish powdery stuff. The problem is: How do I get the remainder of the anode rod out? (By the way, this is only propane fired, there is no electrical element)
Thanks for any help.