During September 1939 the Zoo was bombed, and among many other animals, Kasia the elephant died struck by a shell. Following Warsaw’s surrender, a number of important German officials arrived at the bombed-out zoo. Chief among them was Professor Lutz Heck. Heck was the director of the Berlin Zoological Garden, and he organized that most of the animals was transported to Germany.
The Warsaw zoo, which but for the outbreak of the war would have played host in 1940 to the International Association of Zoo Directors (a tribute to the growing reputation of its director, Jan Żabinski, whose zoo had been in existence for only 12 years),
Jan Żabinski, taken prisoner after being seriously wounded during the 1944 uprising, came back from the internment camp. Some animals were returned to the zoo. Polish soldiers brought back a badger in a barrel: he had dug his way out of the cage during the bombardment and swum across the Vistula. The zoo opened its gates again in 1949.