Hello, I was wiring something and I messed up, as soon as I turned
the heater circuit breaker (to the thing I was wiring) on, there was a
loud bang, smoke and the breaker jumped back to OFF position, that
means, it worked properly, although the part I was wiring, got
damaged. I then disconnected the damaged part.
However, now the circuit breaker appears to "short", that is, even in
the OFF position, some other wires that it controls, are hot!

Can a tripped circuit breaker, get shorted that way in the process, so
that it cannot be turned OFF, and so I should replace the circuit
breaker? Or is something else wrong?

Thank you for any insight, Mark