A man was murdered in his room. His room door was closed and his key was in his pocket. His room has no windows. The bomb was a pickle jar filled with nitroglycerin, no traces of a timer were found. The victim was in the middle of his room watching his favorite show, also the explosion took place in the middle of the room.
Everyone who lives around him has an alibi stating they were outside the building during the explosion. The dead man, pickles, metal lid, and wiring and shattered glass were found. It definitely wasn’t suicide.
How did the murderer pull this off?