West Ham’s clash with Anderlecht descended into chaos as hooligan fans of the Belgian side started throwing flares.
Metro reports that the Belgian side’s supporters kicked off at the final whistle, when their 2-1 defeat was confirmed at the London Stadium. 
They started throwing flares, leading to police attempting to intervene.
The newspaper reports that one police officer was hit with a chair, while another was left with an injury to his arm.
Visiting fans even attempted to invade the pitch, meaning security had to intervene and attempt to return them to their seats.
UEFA has confirmed it will launch an investigation into the issue, and Anderlecht have issued an apology for the way their fans behaved during the game.
The Irons have now essentially confirmed their place in the knockout stages due to beating Silkeborg, meaning they have a head-to-head advantage over the only team that can catch them in the group.
The Anderlecht fans were a disgrace. Throwing flares and ripping up seats and throwing them at West Ham fans could have risked major injury. Although the West Ham fans had nothing to do with it, lazy journalism and the likes of The Daily Mail just love to have a go at us.
The security and Police MUST now search all European teams fans at the turnstiles.
It must be stopped before they get into the stadium.
We cant just rely on the perimeter searches to the Queen Elizabeth Park. They MUST also search every away fan of European teams at the turnstiles, specifically looking for flares.
If not there will be a serious injuries or even a major dissaster.
Were definitely throwing coins, I got hit by one. Also managed to dodge two seats. I even saw a tin of Vaseline chucked too.