MANAGER Kenny Jackett and captain Danny Shittu revealed their frustration after a handful of bottles were thrown onto the pitch during Millwall's win over Aston Villa.
The Football Association has confirmed it will investigate the incident, which saw assistant referee Mark Scholes targeted by four or five objects thrown from the Dockers Stand.
A spokesperson said: "We will be looking into it. We are awaiting the referee's report plus details from an FA crowd advisor who was present."
Shittu joined the majority of Lions fans in condemning the incident after the match. He said: "The bottle-throwing was disappointing but the crowd were there for us and they affected their players.
"Our fans can be really passionate but it doesn't need to go that far. That's why I went over to the side to calm it down a bit.
"The referee could report us and we really don't need things like that as a club."
Jackett added: "We can't condone that and to some degree it was disappointing. On the plus side, the atmosphere was fantastic and the supporters played a big part in a big win for the club.
"From my position pitchside, it's not easy to see the whole thing. It will go off the referee's report and whether he was worried about it during the game.
"It doesn't help us. We want our club to be passionate, we want our fans to be passionate but we can't condone people throwing bottles on the pitch.
"There's a line between supporting your club and creating a passionate atmosphere and we don't want to step over that line."
A Millwall spokesperson confirmed the club would be liaising with police to identify those involved. The FA could decide to issue sanctions if it feels the incident warrants disciplinary action.
"It's regrettable that the actions of three or four individuals should have blighted a very good night for the club," the spokesperson said.
"We will be liaising with the police and studying CCTV footage, which has proved very successful in the past in identifying offenders."