The Daily Mail has revealed the stunning details behind the incident that occurred in the Old Trafford tunnel after the conclusion of the Manchester derby.

According to the publication, a bare-chested Marcos Rojo lead a group of United players - including Antonio Valencia, Ander Herrera, Marcus Rashford, Luke Shaw and Axel Tuanzebe - to the Manchester City dressing rooms after Jose Mourinho was struck in the head by a bottle.

Mourinho had forcibly entered the opposition dressing room to express his irritation at their excessive celebrations after their 2-1 victory, which he said showed a lack of respect.

Although both clubs have said no punches were thrown in the confrontation, the Daily Mail has quoted sources that say punches were indeed thrown, with one catching City midfielder Fernandinho.

The ensuing brawl involved close to 30 people and was compared to a rugby scrum, while City assistant manager Mikel Arteta walked away with a cut on his face after being struck by a bottle.

Non-playing United captain Michael Carrick tried his best to defuse the situation by breaking up the fight and was heard echoing his manager's sentiment, which was that the City players 'lacked respect'.

"Jose went absolutely ballistic when the bottle hit him," a source told the Daily Mail last night. "There was steam coming out of his ears, and then everyone waded in.

"City were celebrating like they'd won the league. They were the better team and deserved to win but you can't start behaving like that."

The FA have asked both clubs to submit their version of events by 6pm Tuesday.