The English Football Association will investigate objects being thrown at Manchester City's star midfielder Kevin de Bruyne at the Emirates Stadium on Wednesday night.
The incident took place during City's 3-1 win against Arsenal, where de Bruyne was targeted while walking around the pitch after being substituted late in the match.
Arsenal confirmed they are also studying CCTV footage and will impose strict sanctions on those responsible if they can be identified.
De Bruyne, who had a goal and an assist on the night, helped City leapfrog Arsenal to go top of the table even as the Gunners have a game in hand.