An internal combustion engine generally includes at least a cylinder; at least an intake valve acting on an intake port for controlling the airflow entering the cylinder; at least an injector for supplying uncombusted fuel to the cylinder; at least an outlet valve acting on a respective outlet port for controlling the flow of the exhaust gases at the outlet of the cylinder; a piston sliding in a linear manner within the cylinder; at least a first spark plug arranged in a position adjacent to the injector and acting within the combustion chamber; a pre-chamber communicating with the combustion chamber; and a second spark plug acting within the pre-chamber; the first spark plug is arranged in an intermediate position between the pre-chamber and the injector.