What did the japanese do to the chinese in nanijing? what did this become know as?

Invasion of Nanking is what it's known as.

By early December, Japanese troops were entering the city of Nanking. On December 9, after the Japanese army failed to get Chinese soldiers to surrender, Japanese launched missile attacks on the city. The Chinese defense retreated to the other side of the Yangtze River.

payments were made after the 1940s.

in the 1980s, a commission held investigations and made recommendations.