Black holes are supposed to be able to have a charge. However, as far as I know, electromagnetic fields travel at c, so that even photons cannot escape a black hole. What about the electric field of an electron? And if we are talking quantum, what about virtual photons?

I think the distinction is that the photons necessary to act as the intermediator ( http://en.wikipedia.org/wiki/Fundamental_force ) have already entered the black hole.

 

I also don't see why the weak and strong nuclear forces couldn't act as well.