The Met Police is investigating after shocking footage has emerged of a Millwall football fan flooring a Tottenham supporter with a punch to the face following the two clubs' FA Cup quarter-final on Sunday (12 March).
The video clip, which was widely shared on social media, shows two Tottenham fans singing "we f*****g hate Millwall" as the visiting club's supporters walked home from their 6-0 defeat at White Hart Lane.
A Millwall fan dressed in a black coat and flat cap can then be seen walking up to the pair and, without warning, punching one in the face.
Cheers can be heard from other Millwall supporters as the victim falls to ground, taking his friend with him.
The Met Police "confirmed that the video circulating on social media has been reported to police".
The incident, in Tottenham's High Road, came after there was a heavy police presence outside White Hart Lane before kick-off, with supporters from both London teams having to be separated as skirmishes broke out. Bangers, flares and bottles were also thrown by fans.
The Met Police confirmed two people were arrested and charged with public order offences relating to the disturbance.
Millwall could also face action from the FA after their fans were accused of singing racist chants at Tottenham forward Son Heung-min during Sunday's match.
Taunts of "DVD" and "he's selling three for a fiver" were directed at the South Korean, relating to racist stereotyping of Asians as traders of bootleg copies of films.
Millwall manager Neil Harris said of the abuse: "I didn't hear anything. Me personally, but the club also, we won't condone that. It's wrong in society and it's wrong in football.
"We came here in the right spirit, to enjoy an FA Cup quarter-final, so if that's proven to have been to the detriment to the competition then I'm sure it will be left to the authorities. We just want people to enjoy the game."