Football hooliganism involves a wide range of behaviour, including:
taunting, e.g. by abusive chanting, sometimes obscene
spitting
unarmed fighting
throwing of objects on to the pitch, either in an attempt to harm players and officials or as a gesture of insult (as when bananas are thrown towards players of black African origin, the racist implication being that they are "monkeys")
throwing of objects at opposing supporters, including stones, bricks, flares and Molotov cocktails.[3][4]
fighting with weapons including sports bats, glass bottles, rocks, rebar, knives, machetes and firearms.[6]
disorderly crowd behaviour such as pushing, which may cause stadium fixtures such as fences and walls to collapse. Similar effects can occur when law-abiding crowds try to flee disorder caused by hooligans.[7