Symptom of bad breaker?
Circuit breakers generally do not leak at all.  But the kind of surge you put on it could have caused the internals to melt together before it blew.

It could also be a breaker further up the line that didn't take it well.  

It could even be the main breaker.

But if you have live voltage on the neutral then it is also likely that somewhere along the neutral connection the surge caused it to become disconnected.  This could be at a wire nut.  Or, perhaps it got hot enough to melt the wire and caused it to separate.

In a case like this I would call a qualified electrician to sort things out.  

You could literally be playing with fire.