I want to know the answer to the following question:
According to Human Rights Watch, how many prisoners were killed on June 29, 1996?
All the background I'm provided with is that "His government's treatment of non-Arab Libyans has also came in for criticism from human rights activists, with native Berbers, Italians, Jews, refugees, and foreign workers all facing persecution in Gaddafist Libya.". Is that enough to answer the question?