Manchester United and Leeds United fans threw kicks and punches in a shocking brawl at Perth's Optus Stadium on Wednesday night.

Mobile phone footage shows a Leeds fan in a fluorescent yellow top push a burly Manchester United fan in a black jacket to the ground.

The Manchester United fan then retaliated as the Leeds fan punched and slapped him in the head while a steward tried to separate them.

As women screamed from the stands, more people joined the brawl including a younger Leeds fan in a white club strip who kicked the Manchester United supporter

As women screamed from the stands, more people joined the brawl including a younger Leeds fan in a white club strip who kicked the Manchester United supporter.

Dozens of police rushed down the aisle of the stand to break up the fight.

Manchester United fan Caitlin Rose, who saw the fight, said Leeds fans had come into the opposition's section of the stadium to look for trouble.

Describing the chaotic and panicked scene, she told Perth Now: 'Some ladies were screaming for police to come as it just escalated so quickly.

She said the fight ruined the night for some fans in that area.

'Some people then left after the police came as it was near the end of the game,' she said.

Manchester United beat Leeds United 4-0 in the pre-season friendly.

The teams have one of the fiercest rivalries in English football, but have not been in the same division for the past 16 years, so this friendly provided a rare opportunity to revisit the old enmity.

Tensions continued on social media after the game as the Manchester United fan group Stretford Paddock accused Leeds fans of racism.

Manchester United and Leeds United fans threw kicks and punches in a shocking brawl at Perth 's Optus Stadium on Wednesday night. Pictured: Leeds fans at the game

Two Leeds fans were filmed jokingly chanting towards a young white Man U fan as he gave an interview with the supporters group.

'We're from Leeds, you're all Chinese,' the Leeds fans sang, referencing the fact that only a small proportion of Man U fans are actually from Manchester.

But the Stretford Paddock did not take the chant lightly, posting the clip on Twitter with the caption: 'Disgusting to see that Leeds fans use casual racism like this. It's not on'.

Several commenters, however, said the chant was not racist and just a light-hearted dig at Man U fans.

'He isn't even Chinese,' one said of the boy in the video.