Abstract: A mechanical safety locking device is electromechanically coupled to an authenticator device, which provides stable interlocking in an active safety position where the interlocking is only deactivated by means of a predefined personalised password associated with a specific user. The mechanical locking device comprises a trigger lever that cooperates with a trigger bar; an interlocking element which is configured to interlock the trigger lever; a displacer element which is adapted to move an interlock bolt between an interlocked position, defined by the physical contact between an appendix and the interlock bolt, and the disinterlocked position, defined by the absence of physical contact between the appendix and the interlock bolt.