Arsenal are investigating an incident of homophobic abuse during Saturday's (Apr 9) Premier League home defeat by Brighton & Hove Albion, the club said in a statement.
Arsenal said two supporters were removed from the stadium and that the club had "stepped up" stewarding operations in the area where the abuse was reported.
"Arsenal should be a safe and welcoming environment for everyone, and we want to be clear that any kind of discriminatory abuse is not welcome at our club," Arsenal said on Wednesday.
"The incidents that were reported are now being investigated by the club, and we will take the strongest action possible against perpetrators who can be identified."
A similar incident marred a match between the same sides at Brighton's AMEX Stadium in October. An Arsenal supporter was issued a three-year banning order following a trial at Brighton Magistrates Court earlier this month.
The supporter was also banned indefinitely from Brighton's stadium.