Manchester United's team bus was pelted with bottles as it arrived at Upton Park before Tuesday's 3-2 defeat.
West Ham has promised to issue lifetime bans to unruly fans after Manchester United's team bus was attacked by supporters prior to kickoff.
Tuesday's stunning 3-2 Premier League victory and farewell to Upton Park was overshadowed as West Ham fans pelted United's coach with bottles on its approach to the stadium.
The pregame scenes and United's late arrival forced kickoff to be delayed by 45 minutes. West Ham is now working with police to as they attempt to identify those involved in the attack.