An emergency meeting for all London Stadium stakeholders has been called after scenes of fan unrest during West Ham's 3-0 defeat to Burnley on Saturday.
Irons supporters protested against club owners David Gold and David Sullivan during the loss, in which Chris Wood scored twice and Ashley Barnes also netted.
West Ham released a statement via their website, saying: "West Ham United have immediately launched a full and thorough investigation into the incidents which marred the second half of today's match and are committed to taking decisive and appropriate action.
"An emergency meeting has been called with all London Stadium stakeholders. There will be no further comment at this time."
The Hammers are now 16th in the Premier League, just three points above 18th-placed Crystal Palace, who played Chelsea in Saturday's late kick-off.
The Independent reported earlier on Saturday that both Gold and Sullivan were instructed by stewards to leave their directors box due to the fan unrest and toxic atmosphere.
Referee Lee Mason also conferred with managers David Moyes and Sean Dyche over whether the complete the game, while Mark Noble was involved in an incident with a pitch invader, the West Ham midfielder throwing the supporter to the floor.
Another supporter picked up a corner flag, ran to the centre circle and planted it into the London Stadium turf.