Holder was trying to protect the stump microphone which relays sound to television when a spectator attempted to grab it.

Warwickshire's chief executive, Dennis Amiss, said the assailant, who was frog-marched off by stewards, was cautioned by police but was unlikely to be prosecuted. Holder indicated that he did not want to take the matter further.

Amiss said: ``We understand that the man detained is a member of the England football supporters' club. He has been told he is not welcome at this ground again and we shall certainly ban him if he tries to get in.

``We only had two ejections from a 20,000 crowd but it is disturbing that an umpire - or a player - should be subject to this treatment.

``At a big game the crowd are encouraged to congregate in front of the pavilion for the presentations and we don't want to stop that. But we have somehow got to make sure that players and officials are able to leave the ground in complete safety.''

Barrie Leadbeater, chairman of the Umpires' Association, said: ``We are concerned about this incident. We will no doubt be raising the issue of safety with the ECB [England and Wales Cricket Board]. With another World Cup on the horizon, it is time to consider what security can be offered umpires and players if spectators get over-enthusiastic.''