LONDON (AFP) - Mayor of London Sadiq Khan added his voice to the condemnation of ugly scenes, as West Ham fans invaded the pitch at the London Stadium and hurled missiles at the English Premier League football club's owners during Saturday's 3-0 defeat by Burnley.
Co-owners David Sullivan and David Gold were forced to flee their seats in the directors' box, as fans crowded aggressively around them with chants of "sack the board" and "you killed our club".
Former West Ham striker and manager Trevor Brooking confirmed that a coin had struck Sullivan's glasses prior to him taking shelter.
"The disturbances at the London Stadium were disgraceful and it's clear that there cannot be a repeat of the ugly scenes witnessed on Saturday," said a spokesman for the Mayor of London on Monday.
"It is up to West Ham to carry out a thorough investigation, together with stakeholders, and take proper action against those supporters who misbehaved."
West Ham said an emergency meeting had been called with all London Stadium stakeholders, which include Gold and Sullivan, whose decision to uproot the club from Upton Park to the site that hosted London's 2012 Olympic Games has caused resentment.
Saturday's events are being investigated by the Football Association and the Premier League.
West Ham captain Mark Noble grappled one fan to the floor, while Burnley players and staff allowed frightened young supporters take shelter on their bench.
The latest incidents are not the first scenes of trouble since West Ham moved to the London Stadium 18 months ago and have raised fears that the club could be punished by having to play a future game behind closed doors.
West Ham's next home fixture is not until March 31 when they host Southampton.
Brooking believes stewarding at the ground is inadequate to cope and believes an extra police presence is required to prevent what he described as scenes from "the bad old days" when hooliganism blighted the English game.
"There weren't sufficient stewards and they couldn't really cope with what was sometimes going back to the bad old days of 25 years ago," he told BBC Five Live.
"The club are obviously going to have to look at things with the local police and make sure that trained stewards and police are in place - you're almost looking at it and saying, 'this is out of control'.
"A lot of the stewards who are on duty on match days are not West Ham people - they're actually stadium people and sometimes until they get a job there haven't had any experience dealing with football crowds."