Manchester United fans could be seen burning an American flag during a protest against the Glazers' ownership outside Old Trafford.
Red Devils supporters sang as the Stars and Stripes were set ablaze in footage shared on social media on Saturday afternoon.
More than a thousand fans gathered on the forecourt outside the stadium's main entrance and near the Holy Trinity statue as they made their feelings known about the botched plans for a European Super League - and the club's American owners.
The Glazers have never been popular among fans since taking charge of the club, but feelings have been heightened after United were forced to backtrack from plans to join a breakaway league, along with the rest of the Premier League's so-called 'Big Six'.
Fans chanted 'Glazers' Out' outside Old Trafford on Saturday, with many amongst the crowd also wearing scarves emblazoned with the hashtag #GlazersOut.
Some fans also climbed the Holy Trinity statue and wrapped a 'Glazers Out' scarf around it, while others let off yellow and green coloured smoke bombs.
There was said to be a limited police presence but a riot van was parked up close to the ground.
A Manchester Evening News reporter at the scene described it as so far peaceful with lots of fans wearing face masks - although some could be seen on the footage without masks.
Fans are also planning to protest ahead of the Premier League clash against Liverpool at Old Trafford a week on Sunday.
In a statement, a spokesperson for the organisers of next Sunday's protests said: "All of the consequences of the debt-ridden Glazer ownership of the club have come home to roost in the last week, with the disgraceful plans to walk away from our roots in English football and walk away from our history and tradition in the European Cup.
"The disgraceful plan was a direct consequence of an ownership structure which is all about money and nothing about supporters.
"United fans demand change. We demand the German model requiring fans own 50% +1 of the club. We demand that the Glazers begin the process to make this happen with immediate effect.
"The last week has shown them the future they dreamed of for Manchester United is not possible and is never going to happen. There will never be a better time to hand majority ownership to the only people who have the long-term interests of the club at heart - the United fans.
"We call on all United fans to come together on the forecourt at 2pm, before the Liverpool game, to collectively make this point in a way the Glazers, and the rest of the world, cannot ignore."