Who Put Bella in the Wych Elm?

On 18th April 1943 four Stourbridge teenagers, Fred Payne, Tommy Willetts, Robert Hart and Bob Farmer discovered the remains of a woman inside a hollow Wych Elm (also known as Scots (Scotch) Elm or Ulmus glabra) in Hagley Wood. It has been suggested that ritualistic magic or even wartime espionage may have been behind this murder mystery that after sixty years is still a focus of interest.