How to remove a movieClip w/reference as a var

How would I remove this attachMovie?

Actionscript Code:

var fm_mc = attachMovie("my_object","my_object" + j,j);

I have tried these codes with no success

Actionscript Code:

fm_mc.unloadMovie(); 
unloadMovie(fm_mc); 
removeMovieClip(fm_mc); 
unloadMovie("fm_mc"); 
removeMovieClip("fm_mc");

Please help, I am using flash 10.2, in flash professional 5.5

Thank you in advance.

It should work! You're probably doing something wrong, so please provide FLA file :D