It's 70 years since the Rape of Nanking, now Nanjing:
Shortly after capturing Nanjing in December 1937, the Japanese army gathered together 1,300 Chinese soldiers and civilians at the city's Taiping Gate. They then killed them.
They blew them up with landmines then doused them with petrol before setting them alight, finally using bayonets to finish off anyone still left alive.
This was just one small incident in what has become known as the Nanjing massacre, a six-week orgy of violence in which tens of thousands of Chinese people died.
A day before the massacre's 70th anniversary, a small group of survivors, dignitaries and visiting Japanese citizens gathered at Taiping Gate to remember the dead.
It is just one of a number of commemoration events being held in Nanjing this week to mark a bloody episode that still reverberates in East Asia today
We only know about the Taiping Gate killings because of the tenacity of Japanese teacher Tamaki Matsuoka, who wanted to know more about the massacre.
With a number of others, she set up telephone hotlines in several Japanese cities in 1997, inviting former soldiers who had served in Nanjing to call up.
The group interviewed more than 200 old soldiers and, from the information it gathered, was able to identify the exact army unit that had carried out the Taiping killings.
Ms Matsuoka told her story at the Taiping memorial ceremony, which took place on a cold, wet Nanjing morning.
Before helping to unveil a small monument, she said she hoped Chinese young people would not forget what had happened in Nanjing.
There is little chance of that. The atrocities carried out by the Japanese in Nanjing, and elsewhere in China during World War II, are drilled into Chinese schoolchildren.