Referees' Association Chairman Paul Field insists the day will come when a referee is killed after Mike Dean was sent death threats at the weekend.
Dean, 52, has not been assigned a Premier League match for the next round of fixtures having asked to be withdrawn after he and his family received threats over his decision to send off West Ham's Tomas Soucek for an alleged elbow against Fulham.
The decisions to show controversial red cards to Soucek and Southampton's Jan Bednarek against Manchester United last week have since been overturned but the referee was widely criticised, and Sportsmail understands the abuse was sent on social media platforms.