The start of the game was delayed for over 30 minutes with large numbers of fans unable to enter the stadium, leading to chaos as police used pepper spray on the crowd.
The first 15-minute delay was announced on a screen inside the stadium, due to the late arrival of fans, and as fans inside noted many empty seats.
The New York Times reported that fans outside of the stadium had been waiting for more than an hour as officials tried to fix a system ticketing error.
Videos posted to social media appeared to show police pepper spraying some of the fans who were holding tickets.
Hundreds of fans are still outside of the stadium after the start time was pushed back.
The game started at 9:36 pm. There were some people in the stadium without seats and standing in the stairways.
The executive director of Football Supporters Europe told the Times that fans at the final bear no responsibility. Thousands are trapped outside the stadium, remaining calm in the face of a completely unreasonable situation.
The European Championship final was held at Wembley Stadium outside of London last year and there were safety issues caused by ticketless fans. A small group of people got into the stadium, though witnesses told the Guardian the number was likely in the hundreds. There was a separate tragedy in 1989 when police ordered an additional entrance to be opened for the FA Cup semi-finals to ease overcrowding. The crush caused by the influx of fans resulted in the death of 97 fans.
The New York Times has a story on the final of the European soccer competition.
England fans force their way into Wembley without tickets.