The Sun says six United players were involved in a 24-man post-match brawl with Chelsea stewards and ground staff.
And Rio Ferdinand and Owen Hargreaves were also guilty of abusing Chelsea staff and match officials in the tunnel in the immediate aftermath of the match.
CCTV footage of those incidents will be handed over to the FA today who confirmed that they have launched an inquiry into events at Stamford Bridge.
FA spokesman Andrin Cooper said: "This will have nothing to do with the referee's report. He would have been in his dressing room a long way from the incident.
"But we will obviously be asking Chelsea to let us see their CCTV footage of the incident."
United players involved in the fracas face fines and possible bans for bringing the game into disrepute.
The club could also be fined for failing to control its players.