I'd like to see that reported in the Chinese newspapers Foreign Worker. It may have an entirely different perspective on it, but only may.
It may have been worse; it could have been a couple of Koreans who perpetrated the grisly murders. I think they're disliked even more intensely by the Japanese.
As for eating human kidneys, a reading of Lord Russell's book, Knights of Bushido, will enlighten the reader of WW2 atrocities perpetrated by soldiers of the Nippopn Imperial Army in the jungles of SE Asia. Removing internal organs, particularly kidneys and livers for consumption, whilst the owners were still alive was quite a common practice.
It seems the practice of dismembering those whose parts were desired for eating whilst the victim is/was still alive has a long pedigree in Japan.
Decapitation of allied soldiers for no good reason, or indeed any reason, was even more common.
This is my last contribution on this specific matter.