The invention provides a two-stroke internal combustion engine, including a crankshaft and two opposed cylinders having their inner ends nearest to the crankshaft. Each cylinder has inner and outer pistons disposed therein and forming a combustion chamber therebetween. Each outer piston is drivingly coupled to the crankshaft by a respective tubular member extending generally axially through the combustion chamber. Fuel injection means are housed within the tubular members are arranged to inject fuel radially outwardly into the combustion chamber.