Police were fortunately on hand to intervene, after initial concerns there would be a shortage of officers forthe clash.
Fights among supporters and segregation issues had marred West Ham's earlier matches this season but improved stewarding by stadium operators London Stadium 185 had helped in recent weeks.
Chelsea had called on the Hammers and cops to "deliver a safe event" for when Antonio Conte's Blues travelled to their London rivals' ground.
Photo / AP.
But those pleas were not carried out as tempers flared and supporters clashed.
Furious fans can be seen being restrained by police in their attempts to get at their counterparts.
And one of the Chelsea faithful was struck in the head by a coin - drawing blood - apparently thrown by a rival supporter.
