The moment a teen lunges at a woman after she apparently calls him a "smelly Nigerian" on the Tube has been caught on camera.
Another passenger starts filming the scene after the pair start arguing, following an accusation from the woman that the man trod on her shoe.
The argument becomes more and more heated, with expletive-ridden exchanges taking place between them.
At the beginning of the footage the woman can be heard saying: "I wouldn't f***ing touch you. You are f***ing s*** on my shoe", and adds that her boyfriend is black in a possible attempt to show she is not being racist.
The man replies with a racist comment of his own, saying: "OK white princess, queen, Kate Middleton!"
They throw insults at each other, and at one point she says: "b******s like you will steal from me" and calls him a "smelly f***ing Nigerian."
As the train pulls into Moorgate, the argument reaches a climax, with the man lunging at the woman after claiming she "hit me on the head with a bottle".
A British Transport Police (BTP) spokesman told the Daily Mail: "There is an allegation of abusive behaviour by the woman towards the man, but that doesn't justify a violent response.
"The man and woman pictured in the images are seen arguing with each other on the video and we're keen to speak to both of them to get their version of events."
The news follows a number of 'racist' incidents occurring on the London Underground; back in November 2013, a Tube passenger was fined £210 for spitting on a Polish man in an apparent racist outburst.
And back in May 2012, a woman who became infamous on the internet after her racist Tube rant was posted on YouTube was jailed for 21 weeks.
Jacqueline Woodhouse was sentenced to the jail term after admitting racially aggravated intentional harassment at Westminster Magistrates' Court.
Racist Tube rant woman jailed for five months
Tube passenger handed £210 fine for spitting on Polish man in 'racist' outburst