An attack on a referee at an amateur football match has been described as the "worst assault on a match official on British soil".
Sunday's incident occurred during a cup game organised by the Turkish Community Football Federation in north London.
The Federation says it is "shocked and disgusted" and "strongly condemns" the incident.
Police told BBC Sport they are investigating an alleged assault on a man in his late 20s.
It is understood the referee suffered only minor injuries.