The irate supporter who managed to infiltrate the England dressing-room after Friday night's game against Algeria in Cape Town could face arrest for trespassing, if local police can find him.
Having been apprehended after offering what an England source described as "a few verbals", he was allowed to slip away again as easily as he had gained admission to the inner sanctum. Fifa will now tighten match security.
"It is of course totally unacceptable that a fan finds his way up to the dressing rooms of any participating team at any competition," the Fifa spokesman Nicolas Maingot said. "Security will be tightened so this never happens again."
The man, who was wearing a red shirt and jeans, was initially apprehended by Fifa officials but then slipped away after he had been handed over to the local police, who have taken over security at Cape Town's Green Point Stadium following a wages dispute between the stewards and the contracted security firm.
The Football Association have denied the suggestion that the intruder was a friend of the England goalkeeper Robert Green, who lost his place to David James for the disappointing 0-0 draw with Algeria.
England must now beat Slovenia on Wednesday to reach the last 16.
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