The Football Association has launched an investigation after Manchester City’s Kevin de Bruyne had objects thrown at him during their 3-1 win at Arsenal on Wednesday evening.
The midfielder was targeted while he was walking around the pitch after being substituted late on.
Referee Anthony Taylor is believed to have mentioned it in his match report.
Arsenal are studying CCTV footage and say they will impose strict sanctions if those responsible can be identified.
“This is unacceptable and will not be tolerated,” added a Gunners spokesperson.
De Bruyne scored and set up a goal as City took over top spot in the Premier League from the Gunners.
The Belgium international posted a picture on social media of himself at Emirates Stadium with the caption ‘beer anyone?’.
Another picture posted by De Bruyne, with a cup in the air near him, had the caption ‘thanks!’.