Fans have been pictured breaking through security barriers at Wembley and running into the ground ahead of the Euro 2020 final.
Dozens of people could be seen suddenly running into the area underneath the stands and up the stairs as staff wearing hi-vis jackets tried to stop them but were overwhelmed.
It is believed up to 100 fans were involved before the area was secured and order restored, Sky Sports News reported.
A spokesman for Wembley Stadium 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.”
Thousands of fans have been gathering at Wembley since this morning, prompting police to urge anyone without tickets to not travel there.
Metropolitan Police said the area is “extremely busy” and officers are on hand “engaging with crowds and to keep people safe”.