A US-made film about the "Rape of Nanking," the massacre of Chinese civilians by Japanese troops during the Second World War in the city now known as Nanjing, opened in Beijing on Tuesday, Reuters reported. The 90-minute movie titled Nanking is co-directed by Oscar-winner Bill Guttentag and producer Dan Sturman. AOL vice chairman Ted Leonsis, who produced the film, said he got his inspiration from Iris Chang's historical book The Rape of Nanking. Drawing on eyewitness accounts, it focuses on the efforts of Nanjing-based US missionaries and German Nazi businessmen to set up a safe zone for Chinese refugees in the city. It will go on general release in the mainland on July 7 to coincide with the 70th anniversary of Japan's full-scale invasion of China. More films on the massacre – which China says claimed 300,000 victims – are set to be released in the run up to the 70th anniversary of the fall of Nanjing on December 13.