One man's racist rant on a London Tube train ended with him knocked out cold from a single punch, with the whole astonishing exchange caught on video.
The incident occurred on the London Underground's Central Line this weekend, with one passenger repeatedly making racist comments to his fellow passengers.
The shaven-headed white man is seen directing a vile stream of invective at a group of black passengers, telling them: "This is my home and you're all going back. You know it as well."
As other passengers argue with him, he doubles down and swings on the handrails singing "they're lesser than us" before telling the black passengers they were his "pets".
The abuse continued until the train pulled into Bank station, when the group of black men prepared to leave the train.
The white man yells "come on" at the group and balls up his fists before one man responds and sends him sprawling unconscious to the floor with a single punch.
Other passengers celebrate, with an older white women telling the group "well done" as the video cuts to a close up of the stricken man's face as one of the black passengers labels him a "d***head" and someone aims a kick at his arm off-camera.
Some passengers move to help the stricken man, asking others to call an ambulance, while some people shout "don't help a racist" and "you deserved that".
A British Transport Police spokesman told the Daily Mail that they were aware of the incident: "British Transport Police are aware of two videos on social media showing an incident on a Central Line Underground train on August 15.
"Enquiries are ongoing, and any witnesses or anyone with information is asked to contact BTP".
The video has had millions of view since it was uploaded to social media, where users revelled in the instant karma the man received.
"This is how you gotta deal with racists," said one.
"If I was in this man's position and I didn't want to be knocked out stone cold in an extremely humiliating manner I would simply not have been racist," said another.
Others decried the violence, saying that we had to "be better than this".