President Xi Jinping condemned any attempts to revise Japan's record of wartime aggression yesterday in a speech marking the country's first national ceremony commemorating the Nanking massacre more than seven decades ago. But he stressed the observance was intended to forge peace, not hatred between the two neighbours. "History will not be altered as time changes, and facts will not disappear because of any chicanery or denials," Xi told an audience made up of local residents, students, veterans and survivors, and foreign guests at the Nanking Memorial Hall in Nanjing , Jiangsu . He added that the days when China could be bullied by foreign countries were long gone. In Hong Kong, Chief Executive Leung Chun-ying gathered with officials at the Museum of Coastal Defence, while Macau also held an official ceremony. Watch: China's Xi says Nanjing Massacre undeniable on 77th anniversary China claims Japanese troops killed more than 300,000 people in the then capital, while a post-war Allied tribunal put the death toll at 142,000. Xi called it a "horrendous crime against humanity and a very dark page in human history". "To forget the past means to betray, and to deny the crime means to relapse," Xi said, in an apparent criticism of some Japanese conservative politicians and scholars. But Xi also struck a conciliatory note, calling for cooperation between the two neighbours. The remembrance day was "not to prolong hatred", but to remind people to hold "firmly to peace", Xi told the audience of nearly 10,000. "We should not simply hate a nation for a small number of militarists who started the invasion war," Xi said. "The responsibility for the war lay with the few militarists, not the people. But people should at no time forget about the grave crimes the invaders committed." In July, Xi spoke at a ceremony that marked the 77th anniversary of the full-scale invasion by Japanese troops in the second world war. In September he attended a ceremony in Beijing for the 69th anniversary of the end of the second Sino-Japanese war. In a front-page editorial, the Communist Party mouthpiece People's Daily called the massacre an "atrocity against humanity, which, like the Nazi massacre in the Auschwitz concentration camp, has become a witness of the tremendous disaster caused by fascism". Professor Niu Zhongjun, of the China Foreign Affairs University, said Xi's remarks demonstrated the importance he placed on historical issues. The emphasise was partly due to "strained bilateral ties, [but] also because to China, any unclear understanding over historical issues may cause further mistrust between the two countries".