London (CNN)The scourge of racism in football showed its face once again Thursday after Arsenal's Europa League victory over Spanish club Valencia was marred by visiting supporters appearing to make Nazi salutes and monkey gestures.
Footage of the latest high-profile incident of racism within football emerged on social media following Arsenal's 3-1 first leg win in London.
Kick it Out, the anti-discrimination body, condemned the gestures as "shocking and inexcusable."
"We utterly condemn such behavior," an Arsenal spokesman told CNN. "It has no place in society or football. We are working with Valencia on this and continue to encourage fans to report incidents and to provide witness statements so effective action can be taken.
In a statement, Valencia said it "publicly condemns and expresses its utter disgust" for those responsible for the Nazi salutes and monkey gestures.
It also added that it was working with the appropriate authorities to identify those responsible, insisting it would take disciplinary action against supporters.
England players suffer racism in Montenegro 01:12
But Valencia was criticized by Kick it Out after stating that while the actions were "absolutely unjustifiable," they would be assessing whether there was any "possible provocations."
"Racist behavior cannot be justified whatever the provocation." Kick it Out told CNN.
"To suggest otherwise casts a doubt on the sincerity of calling such behavior 'absolutely unjustifiable.'"
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Raheem Sterling
Thursday's incident was the latest in a number of high-profile occurrences of racism in football in recent months.
In March, Raheem Sterling urged football's authorities to do more to tackle racism after he and his teammates were subjected to racist abuse during England's 5-1 Euro 2020 qualifying win in Montenegro.
Racists chants were reportedly directed at a number of England players, with defender Danny Rose subjected to monkey chants towards the end of the match
As a punishment, UEFA, European football's governing body, fined Montenegro 20,000 euros ($22,000) and ordered that it play its next qualifying game behind closed doors.
In April, Chelsea took action against three of its supporters after a video appeared to show them singing a song in which they called Liverpool forward Mohamed Salah a "bomber."
Salah also suffered alleged Islamophobic abuse during Liverpool's game at West Ham in February.
