My mother (BA [Hons] McGill, class of '51) used to sing this when my brothers and I were little children, much to our delight. (At that age, we also loved "An Irish Ballad" by Tom Lehrer.) She sang more verses after the ones quoted here, but all I can remember of them is the deathless line "and when they scooped up Olga, she looked more like raspberry jam", which ended a verse in which the bomb was placed in a grocery cart beside a can of Spam.