Simplify the following text for a Grade 15 native English-speaking person.
Original: The prosecution entered indictments against 24 major war criminals and six criminal organizations â `` the leadership of the Nazi party , the Schutzstaffel ( SS ) and Sicherheitsdienst ( SD ) , the Gestapo , the Sturmabteilung ( SA ) and the `` General Staff and High Command , '' comprising several categories of senior military officers .
Simplified: The prosecution brought charges against 24 major war criminals and six criminal organizations - the leadership of the Nazi Party , the Schutzstaffel ( SS ) and Sicherheitsdienst ( SD ) , the Gestapo , the Sturmabteilung ( SA ) and the High Command of the German armed forces ( OKW ) .