London police are investigating after a man was caught on video antagonizing Black passengers on the London Underground with a racist rant.

The man police are investigating was knocked out with a single punch.

Videos posted to social media show the man, who is white, shouting at a group of Black men.

He can be heard telling them, “this is my home and you’re all going back” before yelling, “you’re black!”

As the train approached the platform of Bank Station, the group of men tried to walk by him to leave the train.  The accuser stood up to them and balled his hands into fists.

When the men step on the platform, one of the guys reached back to throw a single punch to the white man’s jaw. He can be seen collapsing to the floor and appears to be unconscious.

A spokesperson for British Transport Police told The Independent that they were “aware of two videos on social media showing an incident on a Central Line Underground train on August 15. ”

Throughout the incident, several other passengers in the same carriage tried to diffuse the situation. One woman interrupted him to say, “look, you’ve had your five minutes of fame, now f**k off and get out of the train.”

Watch the video below: