Abstract: An internal combustion engine includes an intake valve for controlling a cylinder intake port; an exhaust valve for controlling a cylinder exhaust port; first and second valve lifters coupled to the intake and exhaust valves, respectively, for cyclically opening and closing the intake and exhaust valves during normal engine operation; and an actuating device for contacting the exhaust valve and for operating the exhaust valve independently from the second valve lifter. The actuating device has a withdrawn position and a valve-contacting position. In the withdrawn position the actuating device is out of contact with the exhaust valve and in the valve-contacting position the actuating device is in contact with the exhaust valve. There is further provided an electromagnetically-operating setting device having an inoperative position assumed for a normal engine operation and an operative position assumed for an engine-braking operation.