Keyed device for operating locks (S), incorporating euro profile i cylinders (E), suitable for installation on security doors, armoured doors and the like, and comprising at least one cylinder-operated deadbolt (P), where the cylinder (E) comprises a cam (C) that can be rotated in either direction, respectively to open or close at least one deadbolt (P), and where the device in question comprises: - one mechanism for operating the cam (C) comprising: an actuator plug situated inside the euro profile cylinder (E) i and coaxial with the rotation axis of the cam (C), which causes the cam to rotate; a manipulator head , connected to the actuator plug , and which causes the plug to rotate; mechanical combination means for blocking and releasing the rotation of the manipulator head and the connected actuator plug ; - an opening/closing assembly , accessible from the exterior of the security doors, armoured doors and the like, for operating the manipulator head and the mechanical combination means , where the opening/closing assembly comprises: an outer shell , incorporating an axial pass-through cylindrical seat characterized in that the axial pass-through cylindrical seat houses a rotor coaxial with the manipulator head and the actuator plug , where the rotor is able to slide axially toward the manipulator head , in opposition to the spring-loaded components which retain it, when at rest, against a shoulder within the cylindrical seat ; a defender block , for impeding external access to the manipulator head , supported by a pin inside the rotor , with the ability to rotate on an axis perpendicular to the rotation of the rotor , where the defender block is partially accessible externally and close to the manipulator head with its corresponding internal part, and where the defender block comprises a first profiled face that can be stably paired with a removable flat key , and a second profiled face , diametrically opposite to the first, that can be provisionally paired with a locking/unlocking tool , and where the defender block is able to rotate between at least two characteristic positions, one where the first profiled face is turned outward and can receive the flat key , and another where the first profiled face is turned toward the manipulator head while the second profiled face is turned outward and can receive the locking/unlocking tool , which can be manually operated on to achieve: the axial translation of the rotor - defender block - flat key assembly , so that the key engages with the mechanical combination means for releasing the rotation of the manipulator head ; the rotation, in one or the other direction, of the rotor-defender block - flat key - manipulator head - actuator plug assembly , with consequent rotation in the same direction of the cam (C) to open or close the lock (S). - one mechanism for operating the cam (C) comprising: an actuator plug situated inside the euro profile cylinder (E) i and coaxial with the rotation axis of the cam (C), which causes the cam to rotate; a manipulator head , connected to the actuator plug , and which causes the plug to rotate; mechanical combination means for blocking and releasing the rotation of the manipulator head and the connected actuator plug ; - an opening/closing assembly , accessible from the exterior of the security doors, armoured doors and the like, for operating the manipulator head and the mechanical combination means , where the opening/closing assembly comprises: an outer shell , incorporating an axial pass-through cylindrical seat characterized in that <EOS>