An Arsenal fan was allegedly thrown down a staircase at the London Stadium after angering West Ham supporters by sitting in the home end. 

The Gunners visited their London rivals on Sunday afternoon in search of a huge three points as they close in on their first Premier League title in 22 years.

And a late Leandro Trossard strike secured a crucial victory for Mikel Arteta's side, who now must beat Burnley at home and Crystal Palace at Selhurst Park to clinch top spot.

Three thousand Gunners fans enjoyed the win from the comfort of the away end, but footage that has gone viral on social media suggests some away supporters infiltrated home areas of the stadium.

Shocking video footage has shown a male spectator being thrown down a flight of stairs in the upper echelons of the stadium, with a handful of angry fans chasing after him. 

Football grounds across the country adopt strict rules forbidding the purchasing of tickets in opposing ends of stadiums, due to the increased threat of violence among fans.

The Met Police said in a statement: 'Met officers arrested four people at the London Stadium on Sunday, 10 May following the fixture between West Ham United and Arsenal.

'Two men – aged 48 and 36 - were arrested on suspicion of affray and assault, while one teenage boy was arrested on suspicion of racially aggravated assault. All were taken into custody where they remain. Police continue to work with the football club while enquiries into the respective incidents continue.

'Another man, aged 31, was arrested for possession of a Class B substance.'

West Ham have been contacted for comment. 

While there were heated scenes in the stands, there was also controversy on the pitch with West Ham denied a late equaliser following an intervention from VAR. 

Callum Wilson thought he had rescued a point for the Hammers in stoppage time, but his goal was ruled out following a lengthy delay after his team-mate Pablo was adjudged to have fouled David Raya in the build-up.

VAR official Darren England spent several minutes looking at replays of the incident, before he sent referee Chris Kavanagh to the screen to review it further.

There, Kavanagh ruled that Pablo had his arm across Raya's chest, impeding him from catching the ball or parrying it away, with Arsenal going on to see the game out and open up a five-point lead over Pep Guardiola's side to close in on the Premier League title.

It was one of the most dramatic moments in Premier League history, but Man United legend Peter Schmeichel felt the officials made a huge mistake.

'That decision today, it's just so wrong on so many levels,' he fumed on Viaplay. 'What really makes me angry is that Arsenal would never be top of the league if that's a free kick.

'That's how they've scored so many goals by blocking people, holding people, doing all kind of things, and then we get to this point... it takes VAR five minutes.

'Darren England the VAR official, (it takes him) five minutes. He starts the replay over and over again. That in itself puts so much doubt into that decision. It cannot be a free kick, it cannot.'

Schmeichel continued: 'I think it's so wrong, I just don't understand why all of a sudden that's a free kick, because it's not been for any teams all the way throughout the season.

'All of this, it's just crazy, and that decision today is just so wrong on so many levels.'

If Arsenal had drawn the game they would have only been three points ahead of City, who have a game in hand.

But the title race now remains firmly in their hands while West Ham are even closer to relegation, with the Hammers a point behind Tottenham having played a game more.

West Ham captain Jarrod Bowen was understandably frustrated after the match as he hit out at the length of the delay that led to the VAR overturn.

He said: 'Because we're on the receiving end, we're going to feel hard done by. Goalkeepers are protected more than outfield players. There's lots of holding and grappling going on in the box. The keeper has to expect contact, there's going to be tussles.

'I'm sure we could go back through every single game and find goalkeepers being fouled and not getting decisions. If you're going to give it, you have to give it to every single one that happens week in, week out. Where's the consistency?

'When you look at the screen for five minutes, you'll find something. I'm sure if you look long enough, you'll find something. Do I think it's the right decision? No.'