Arsenal have opened an investigation into racist abuse from a supporter toward Napoli centre-back Kalidou Koulibaly.

Per the Mirror's Alex Richards, Arsenal are looking into a video posted to social media during Thursday's clash between the two sides at the Emirates Stadium, which depicted a fan racially abusing the Senegalese defender.

Richards relayed the Gunners' statement on the matter:

"We utterly condemn use of this type of racist language and have launched an investigation to identify the culprit.

"We operate a zero tolerance approach, and anyone behaving like this is not welcome at Arsenal and will be banned from matches.