I'm not sure if this is appropriate for /r/AskHistorians, but I have a first-hand account from my grandfather that he shared with me right before he died. It's not exactly this, but it is quite similar:
My grandfather was a radio operator about a B-17 in the 8th Air Force during World War II. He was stationed in England and his bomber was tasked with flying solo over the European mainland to take weather readings so that troops and other air resources could know what to expect.
He told me that one night while they were on base in England, the officers decided to give a "treat" to the men on station. Apparently they shipped in a large number of local women into the base and arranged a party with food and dancing for the men so they could relax. Anyway, the party was only for white soldiers and the women were all white as well. The black soldiers became very upset that they were not given a similar accommodation and, in protest, several decided to crash the party.
They entered the party and started cutting in and dancing with the women wherever they could as well as eating the food and, as my grandpa described it, "causing a scene." So, in response, the white men proceeded to gang up on this group of black soldiers. They beat the crap out of them.
That's bad. It gets worse.
They took those black soldiers which they had beaten and loaded them into a truck. They drove down to cliffs by the ocean. They threw them off into the sea.
My grandfather's exact words were "that night every single one of them went flying off the white cliffs of Dover."
I asked him if the men who did that were ever charged with murder and he said that the commanding officers never mentioned it and nothing was ever done. Those black soldiers, whoever they were and however many, just disappeared, likely chalked up as KIA by the Army.
It bothers me. He has been dead for years and so is my grandmother. He told me all of that face to face before he died and basically said it felt good to get that off his chest. I don't know if that counts as valuable history, but it was a first-hand account from a soldier who claims he saw something very evil happen during that war.