media captionVideo shows fans breaking through a Wembley Stadium entrance before the final
The Football Association (FA) will conduct a full review after a "large number of drunken yobs" tried to force their way in to Wembley without tickets ahead of the Euro 2020 final.
Fans fought with stewards and police as they attempted to break through gates.
FA chief executive Mark Bullingham apologised to legitimate fans who were affected and said the security team had "never seen anything like it".
The Metropolitan Police said it worked with security to prevent breaches.
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Mr Bullingham said he was not sure those who broke in were real fans.
"There were a large number of drunken yobs trying to force their way in, we run a stadium not a fortress," he said.
"I have to apologise to any fans whose experience was affected and any of the team who had to cope with this."
He said the FA would work with the police to ban anyone who had forced their way in and to prevent such an event happening again.
Lis Nixon, 62, from Oxfordshire, who was at the match, said it was "horrible" and "put you off going".
She said she was pushed and crushed while queuing to get into the stadium and said once inside, there were large numbers of ticketless fans in rows and blocking exits with some people so drunk they had fallen to the ground and were just left there.
She said the stewards were "overwhelmed" and had "lost control" of the situation.
image copyrightRoberta Cuppariimage captionRoberta Cuppari (right) with her friend at Wembley
Italy supporter Roberta Cuppari said she and her friend had to watch the match crushed in a corner while being sworn at and abused after ticketless fans took their seats and refused to move.
"It was the worst thing I have ever seen," said the 38-year-old mother-of-three. "There were people urinating, people doing drugs."
She said people had pushed through behind them at the entrance, refusing to show their tickets or proof of Covid tests but security had not done anything, even when she had called for help.
Ms Cuppari, from Weybridge, Surrey, said it was unsafe and she was glad not to have brought her seven-year-old son, who would have been "put off football for life".
Police initially denied anyone without a ticket had gained entry, saying there were "no security breaches by people without tickets".
In a later statement, a stadium spokesperson said: "There was a breach of security and a small group of people got into the stadium.
"We are now working closely with stadium stewards and security to remove these people. Anyone inside the stadium without a ticket will be instantly ejected."
Health minister Edward Argar told Sky News action would be taken against those who had broken the law, adding that it was sad a "tiny minority" brought sport into disrepute and said it was not reflective of the fans of the national team.
A large crowd had also been trying to enter the fan zone in Trafalgar Square without tickets shortly before kick-off, the Met Police said.
Police said they had been "engaging with the crowd and telling them to disperse".
Some people inside Wembley said there had been fans standing on the concourse for the entire first half, watching the match.
After the match, riot police could be seen breaking through crowds outside Wembley Stadium as fans departed.
Beer bottles were thrown amid chants against Italy. The Met Police said there had been 45 arrests by officers policing the final, with 19 officers injured "while they confronted volatile crowds".
Home Secretary Priti Patel said the "violent minority" who assaulted officers were not "true fans".
'Anarchy descended on Wembley'
Former England striker Chris Sutton told BBC 5 Live the situation had been an "absolute shambles".
Mike Keegan, sports news correspondent for the Daily Mail who was there with his father as a fan, said he had "never seen anything like it", describing those who forced their way in as "aggressive, menacing people".
He told BBC Radio 5 Live: "It felt like anarchy descended on Wembley last night."
The FA and politicians have also condemned the racist abuse aimed at penalty takers Marcus Rashford, Jadon Sancho and Bukayo Saka.
Prime Minister Boris Johnson called it "appalling" while English football's governing body said anyone behind such "disgusting behaviour" was not welcome following the team.
The Duke of Cambridge tweeted that he was "sickened" by the "totally unacceptable" abuse.
'Inevitably the situation boiled over'
By Phil McNulty, BBC Sport chief football reporter
The unsavoury scenes at Wembley before and during England's Euro 2020 final defeat to Italy were the result of an uneasy, threatening undercurrent of tension that had been building up throughout the day.
Several hours before kick-off, thousands of fans, many fuelled by alcohol, were packed into areas around the stadium in an increasingly frenzied atmosphere that always threatened to get out of hand.
Security was ineffective and it is rare at a major final for supporters to be able to get so close to the stadium without tickets. I was offered money for my accreditation lanyard just yards from the media entrance – unthinkable at any such showpiece event I have previously attended.
Inevitably, the situation boiled over into the frightening sight of barriers being stormed by scores of ticketless fans desperate to get inside Wembley, with children left terrified, others knocked to the ground, aisles full and the area reserved for disabled spectators swamped with supporters looking for anywhere to sit.
Fans who had legitimately paid to watch England's first major final for 55 years were left struggling to watch the game.
Stewards, perhaps understandably, were overwhelmed by the numbers they were having to deal with. It certainly did not appear to be a "small group" as originally stated.
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