Fuel injector of an internal combustion engine and internal combustion engine

An internal combustion engine, comprising:

• a cylinder equipped for igniting, with a first fuel, a second fuel for combustion in the cylinder;
• and
• a fuel injector for the cylinder comprising:
• a main body;
• a first nozzle needle moveably guidable in a first needle guide;
• a first needle fuel chamber that interacts with the first nozzle needle for a first liquid fuel, which can be coupled via first channels to a combustion chamber of the cylinder, wherein the first channels are connected to the first needle fuel chamber via first internal openings;
• a second nozzle needle moveably guided in a second needle guide;
• and
• a second needle fuel chamber that interacts with the second nozzle needle for a second liquid fuel, which can be coupled via second channels to the combustion chamber of the cylinder, wherein the second channels are connected to the second needle fuel chamber via second inner openings;
• wherein the first internal openings are arranged on a first circular contour and the second inner openings on a second circular contour extending concentrically about the first circular contour.