British police made 49 arrests and said 19 of its officers were injured after confronting volatile crowds near Wembley Stadium while policing the Euro 2020 final between Italy and England on Sunday.

Fans clashed with each other and officials, breached security cordons and charged into the perimeter area of Wembley before the start of the match, which Italy won after a penalty shootout.

"We made 49 arrests during the day for a variety of offences. We will have officers on hand throughout the night", the Metropolitan Police said on Twitter.

A day of alcohol-fuelled festivities had begun with rowdy scenes in central London and tens of thousands made their way to the national stadium for the game, with flares being let off in railway stations and singing on trains.

Around two hours before the game, fans burst past stewards and some reached the concourse while bottles were thrown in from outside the perimeter.

Some security staff were attacked, witnesses told Reuters, and entry to the stadium was halted for over 20 minutes while order was restored at the entrances.

Outside the ground, several thousand fans continued drinking and partying in the area immediately adjacent to the entry points with empty beer cans lining the street.

Police said they helped the security teams at the ground.

"Wembley security officials have confirmed there were no security breaches of people without tickets getting inside the stadium," the Metropolitan Police said on Twitter.

Some witnesses, however, said they saw isolated cases of fans running through the seating areas inside the ground being chased by security.

Inside the stadium, there was a party atmosphere with fans singing "Sweet Caroline" and "Three Lions" - the unofficial anthem of the England team.

Police had previously urged supporters not to travel to Wembley if they did not have match tickets, and complained of multiple cases of flares being set off within the vicinity of railway stations in London.

Across the capital, many had set up camp early with thousands queuing to get into pub gardens before lunchtime and others packed into city squares. Hundreds of fans draped in red and white flags threw and smashed bottles in Leicester Square earlier in the day.

Hours before the 8 p.m. local kick-off, Wembley Way was crammed with supporters all the way from the underground station to the stadium.

Beer cans and bottles flew through the air as acrid smoke from flares drifted through the crowd and supporters, dressed in England shirts of various vintages, sang and chanted.

Gus McKay, a 53-year-old England fan from Bradford-on-Avon, joined the party at Leicester Square in central London.

"It feels incredible," he said. "I've been waiting all my life (to reach a final)."

Dave Woodall from York echoed the sentiment: "I was one when we won the World Cup and it's a dream that I never thought would happen," he said.

"So I'm like a kid at Christmas. It's the best feeling ever. I had to come down for the day, I couldn't miss this."

England are bidding to win their first major title since lifting the 1966 World Cup.