In a complaint filed before Easter with the Berlin public prosecutors office, Green party politician Claudia Hämmerling claimed the zoo has broken animal protection laws, alleging that more than 100 hundred animals have "disappeared" from the zoo in the last decade.
Among these animals, Hämmerling said her research shows that tigers were delivered to China where they were allegedly slaughtered and used to make potency drugs. In another incident, Hämmerling said four black bears were sent to a place in Belgium where there was a slaughterhouse, but not a zoo. The fate of several hippos is also unknown, she said.
Blaszkiewitz, who has directed the zoo's Tierpark facilities on the eastern outskirts of Berlin since 1991 and has headed the city's main Zoologischer Garten facilities since February 2007, said the allegations were false.
Blaszkiewitz said the four cats had become feral and could have spread dangerous disease to other animals and zoo patrons. "I broke their necks in a suitable fashion," Blaszkiewitz told Berlin tabloid daily B.Z..
Spokesperson for the Berlin animal protection agency, Marcel Gäding, responded that according to new information, the event was not isolated.
Blaszkiewitz received and anonymous death threat on Friday and police were notified, zoo spokesman Detlef Untermann told press agency DPA.
Regarding the ethical debate, president of the German association for zoo directors, Gisela von Hegel said, "The life and death of wild animals in zoos must be handled in public with transparency." Von Hegel, a veterinarian and director of the Karlsruhe Zoo continued, "Wild animals must not be considered playmates and handled like house pets."
Von Hegel gave an example of the Nuremberg Zoo, where according to German daily Süddeutschen Zeitung, an antelope was killed to fed to lions. Actions like these may be necessary because the birthrate in zoos can often be difficult to control as necessary, she went on.
Von Hegel declined to comment on the "disappeared" animals in Berlin.
The Berlin Zoo has enjoyed record revenues in recent years under Blaszkiewitz's leadership thanks to the popularity of their famous polar bear Knut.