Anderlecht manager Felice Mazzu has apologised for the behaviour of his club’s fans.
The Belgian side’s supporters appeared to throw flares last night, while newspaper reports have suggested that a police officer was injured during the trouble. 
The Evening Standard reports that away fans not only clashed with police but also ripped up seating in the away end and there were allegations of coins being thrown at home supporters.
On the pitch, the Hammers won 2-1, thanks to goals from both Said Benrahma and Jarrod Bowen.
At full-time, sections of the Anderlecht support attempted to invade the pitch, leading stewards to intervene.
The Belgian club’s manager, Mazzu, was aware of the trouble and has apologised for it.
Quoted by the aforementioned newspaper, he said: “We want to apologise to West Ham.
“We don’t tolerate this and strongly condemn this behaviour. We will take it up with Uefa and our own fans.”
UEFA has since confirmed that it will launch an investigation into the incident, as they attempt to apportion wrongdoing. It is possible the Hammers could be fined, as they were last season when trouble flared in Europe.
One major element that has been totally overlooked regarding the disgraceful actions of the Anderlecht fans, was the fantastic re-action or more importantly non re-action of the West Ham fans. They should be commended for staying calm and not retaliating in the face of severe violent provocation. The press would of have had a field day if our fans had retaliated, yet nothing has been said about the exemplary reaction of the West Ham fans.
Maybe an article Hugh/Sean may go some way to highlighting the positives of the true West Ham fans.
Whisper it quietly, but did the erection of the wall between the away fans and the supporters in the West Stand prevent a major violent confrontation?
The wall was erected to prevent goading and confrontation between the away fans and the vocal part of the home support.
Because of the wall the Anderlecht fans had no one to directly engage with their violent behaviour. I feel that if the wall wasn’t there, the possibility of confrontation would have been greatly increased. When the Anderlecht fans started throwing flares and seats, they could only do this to the home fans in the Trevor Brooking stand, who were further away and don’t have such a direct view of each other. Also fans here are a little less boisterous.
I do feel had the wall not been there, it could have resulted in a far worse incident, than it already was.