From the FA website:
Following the game between Chelsea and Arsenal on Saturday [19 September 2015], The FA has taken the following disciplinary action.
Diego Costa has been charged for an alleged act of violent conduct which was not seen by the match officials but caught on video. The Chelsea forward was involved in an incident with Arsenal’s Laurent Koscielny in the 43rd minute of the game. He has until 6pm tomorrow [Tuesday 22 September 2015] to reply.
Off the ball incidents which are not seen at the time by the match officials are referred to a panel of three former elite referees. Each referee panel member will review the video footage independently of one another to determine whether they consider it a sending-off offence. For retrospective action to be taken, and an FA charge to follow, the decision by the panel must be unanimous.
Arsenal defender Gabriel has been charged with improper conduct for his behaviour following his dismissal, whilst team-mate Santi Cazorla has been warned for his behaviour following his sending off.
Finally, both clubs have been charged for failing to control their players under FA Rule E20.
Both clubs and Gabriel have until 6pm on Thursday [24 September 2015] to reply.
Following the game between Chelsea and Arsenal on Saturday [19 September 2015], The FA has taken the following disciplinary action.
Diego Costa has been charged for an alleged act of violent conduct which was not seen by the match officials but caught on video. The Chelsea forward was involved in an incident with Arsenal’s Laurent Koscielny in the 43rd minute of the game. He has until 6pm tomorrow [Tuesday 22 September 2015] to reply.
Off the ball incidents which are not seen at the time by the match officials are referred to a panel of three former elite referees. Each referee panel member will review the video footage independently of one another to determine whether they consider it a sending-off offence. For retrospective action to be taken, and an FA charge to follow, the decision by the panel must be unanimous.
Arsenal defender Gabriel has been charged with improper conduct for his behaviour following his dismissal, whilst team-mate Santi Cazorla has been warned for his behaviour following his sending off.
Finally, both clubs have been charged for failing to control their players under FA Rule E20.
Both clubs and Gabriel have until 6pm on Thursday [24 September 2015] to reply.