There were chaotic scenes in central London – with some fans even trying to force their way into Wembley Stadium – ahead of the Euro 2020 final.
Officials confirmed there had been “an incident” at the outer security perimeter area, after footage showed a crowd of supporters making a dash to get inside.
But a spokesperson for Wembley Stadium said there had been no security breaches of people getting in without tickets.
They said: “We are dealing with an incident that occurred at the outer security perimeter area of the stadium, with support from police.
“Safety measures were quickly activated in the relevant areas and there were no security breaches of people without tickets getting inside the stadium.”
The Metropolitan Police said they supported the security teams at Wembley Stadium.
Fans in Leicester Square were earlier seen throwing bottles and cones and the area was left littered with rubbish.
Fans have been urged to stay safe and look after each other.
Police said there had been people “jumping off street lamps or hoardings” and warned “this could easily end in injury”.
Huge crowds of people have been in party mode outside the stadium and across London throughout the day.
But some boisterous supporters even climbed on top of a bus outside Wembley, while others outside King’s Cross station in the capital let off red and white smoke during the build-up.
British Transport Police said there had been “multiple cases of flares being set off within the vicinity of railway stations” in the capital and warned that “these incidents are offences and will be investigated”.
Both UEFA and the Football Association have denied reports fans had managed to gain entry to Wembley without tickets after videos posted online showed supporters breaching security cordons.
Tournament organisers UEFA have told the PA news agency everything remains “under control” and no-one could enter the stadium without a ticket.
An FA spokesperson added: “We are dealing with an incident that occurred at the outer security perimeter area of the stadium, with support from police.
“Safety measures were quickly activated in the relevant areas and there were no security breaches of people without tickets getting inside the stadium.”
A Wembley 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.”
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