China-Japan tensions rise on the 75th anniversary of the Nanjing massacre

Sirens wailed in the Chinese city of Nanjing, 75 years after Japanese troops committed mass killing and rape in the city. China says 300,000 civilians and soldiers died in a spree of killing, rape and destruction in the six weeks after the Japanese military entered its then capital on December 13, 1937.

Nearly 10,000 people sang the Chinese national anthem at a commemoration at the Nanjing Massacre Museum, as soldiers in dress uniforms carried memorial wreaths across a stage and officials urged remembrance of the past.

 An elderly woman cried as she placed flowers by the names of family members listed among the victims on a grey stone wall, and a group of Chinese and Japanese Buddhist monks chanted sutras to pray for world peace.

Some ultra-conservative Japanese politicians dispute that atrocities ever took place in Nanjing. On its website, the Japanese foreign ministry concedes only that "the killing of a large number of non-combatants... occurred" and says that "it is difficult to determine which the correct number is".

Fewer than 200 survivors remain, according to Chinese estimates. One of them, Li Zhong, 87, said he can never forgive, recalling how people had to restrain a man who grabbed a knife to kill Japanese soldiers after his wife was raped. "There are fewer and fewer of us survivors every year," he said. "We must never forget history."

Kai Satoru, the son of a Japanese soldier who served in China, was among the hand-picked audience. "I am here to admit the crimes. They (Japanese soldiers) competed to kill people," he said.

The 75th anniversary has taken on added meaning given the poor state of bilateral ties. Japan scrambled F-15 fighters after a Chinese state-owned plane entered airspace over islands claimed by both countries. Chinese government ships have moved in and out of waters around the islands - known as the Senkaku Islands in Japan and the Diaoyu Islands by China - for more than two months. But it was the first time that Chinese planes have ever intruded into Japanese airspace, according to the defence ministry in Tokyo, while China defended its right to overfly what it says is its own territory.

A Nanjing massacre survivor is pictured between Chinese Buddhist monks at a ceremony for the victims on the 75th anniversary of the Nanjing massacre at the Memorial Museum in Nanjing

A Nanjing massacre survivor cries as she pays her respects to victims on the 75th anniversary of the massacre

Japanese Buddhist monks pray for the victims on the 75th anniversary of the massacre at the Memorial Museum in Nanjing

A Buddhist monk prays at a wall inscribed with the names of Nanjing massacre victims

Chinese military personnel attend a ceremony for victims on the 75th anniversary of the Nanjing massacre

People gather to mourn for the victims of 1937 Nanjing Massacre

A giant cross is seen at the Memorial Museum in Nanjing

Sculptures portraying scenes of horror are seen at the entrance to the Memorial Hall of Victims of the Nanjing Massacre

A school boy holds a flower during a ceremony to observe the 75th anniversary of the Nanjing Massacre

Visitors to the Memorial Hall look at images of the Nanjing massacre

People look at the faces of some of the known victims of the massacre