A safety arrangement for selectively disabling a firearm is provided. The firearm includes a handle, a trigger, a hammer, and a barrel. The hammer, in an unlocked condition, is movable into a functional position for being actuable by the trigger for striking a magazine causing firing of a bullet and, in a locked condition, is mechanically locked so that it cannot be actuated by the trigger for causing firing of a bullet. The arrangement includes a control unit adapted in the locked condition to lock the hammer and, in the unlocked condition, to unlock the hammer; an electronic decoder unit adapted to decode input signals and to provide corresponding output signals; an electronic driver stage being adapted on receipt of the output signals from the electronic decoder unit, to cause corresponding operation of the control unit for locking and unlocking the hammer as the case may be; and a keypad unit having a number of key buttons, the key buttons being adapted on operation thereof to provide input signals to the electronic decoder unit when the keypad unit is electrically coupled thereto.