The arrest of former Bosnian Serb leader Radovan Karadzic and his expected transfer to The Hague throws a renewed spotlight on the prosecution of war crimes. But what exactly are war crimes? What body of laws do they refer to and who has the right to try a suspect for such crimes? Radovan Karadzic is set to follow Slobodan Milosevic to The Hague The concept of war crimes is a recent one. Before World War II, it was generally accepted that the horrors of war were in the nature of war.

But during World War II the murder of several million people - mainly Jews - by Nazi Germany, and the mistreatment of both civilians and prisoners of war by the Japanese, prompted the Allied powers to prosecute the people they believed to be the perpetrators of these crimes.

The Nuremberg trials in 1945 and 1946 led to 12 Nazi leaders being executed.

A similar process started in Tokyo in 1948. Seven Japanese commanders were hanged, though the Allies decided not to put Emperor Hirohito in the dock.

These trials were essentially the precedents for the cases that the modern-day tribunal in The Hague hears.