In one disturbing moment a flare was launched into the stand behind the goal causing causing a fiery explosion in the Athens Olympic Stadium.
Blood can be seen dropping from the heads of several men inside the stadium.
Riot dressed in full armour are pictured hitting supporters with their batons as horrified fans watched on.
No arrests were immediately reported.
AEK currently sit bottom of Group E having lost their opening four games, and can no longer advance to the knockout stages.
Meanwhile their opponents Ajax are on the brink of sealing their place in the last-16 having picked up two wins and two draws.
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