The fistfights between Nazis and the main characters (and other people) are particularly intense near the end of the movie. It would become clearer to a young child through many scenes where the Nazis arrested, beat up, or even killed people, that the Nazis can torment, imprison, even kill everyone, and thus the big fight scene near the end of the movie is somewhat more scary.
Later in the movie, a man is murdered, a main character is seen dead (after he commits suicide in his bathtub) with a puddle of blood near him, and a person opens a box which holds the cremated ashes of a person murdered by the Nazis.
However, the level of violence does not approach full battle scenes, and is not sustained long in a scene.