There were ugly scenes during West Ham's 2-0 win over Rapid Vienna in the Europa League on Thursday.
Trouble broke out in the visiting supporters' end after Declan Rice put the Hammers in front at the London Stadium in the first half.
Some visiting fans tried to storm the home section after the goal, jumping the barriers before being forced back by stewards and then police.
Both sets of supporters were seen lobbing objects at each other, including a giant water cooler bottle.