What you need to know:
- UEFA said French police had fired tear gas to disperse thousands of frustrated fans who were building up outside the Stade de France as a result of the fake tickets issue
European football governing body UEFA blamed "fake tickets which did not work in the turnstiles" for a delay of over half an hour to the start of Saturday's Champions League final between Liverpool and Real Madrid in Paris.
UEFA said French police had fired tear gas to disperse thousands of frustrated fans who were building up outside the Stade de France as a result of the fake tickets issue.
But English giants Liverpool said they were "hugely disappointed" that their supporters had been subjected to an "unacceptable" breakdown of the security perimeter at France's national stadium.
The final of Europe's most prestigious club competition was supposed to kick off at 9:00pm (1900 GMT) but was pushed back due to the queues of mainly Liverpool fans who could not get into the ground.
"In the lead-up to the game, the turnstiles at the Liverpool end became blocked by thousands of fans who had purchased fake tickets which did not work in the turnstiles," UEFA said in a statement.
"This created a build-up of fans trying to get in. As a result, the kick-off was delayed by 35 minutes to allow as many fans as possible with genuine tickets to gain access.
"As numbers outside the stadium continued to build up after kick-off, the police dispersed them with tear gas and forced them away from the stadium."
UEFA said they were "sympathetic" to the fans affected and would review the situation together with local police and authorities, as well as the French Football Federation.
French police sources told AFP that supporters tried to force their way through the first ticket checkpoint outside the stadium situated in the northern Paris suburb of Saint-Denis.
Tear gas was fired by police after several dozen people attempted to climb over barriers, according to an AFP reporter on the scene, with about 20 people succeeding in clearing the fence and getting into the ground.
Thousands of supporters were still massed outside the stadium with half an hour to go to kick-off.
Liverpool, however, were adamant fans had been badly treated ahead of a match that Real won 1-0 thanks to Vinicius Junior's 59th-minute goal.
"We are hugely disappointed at the stadium entry issues and breakdown of the security perimeter that Liverpool fans faced this evening at Stade de France," the English club said in a statement.
"This is the greatest match in European football and supporters should not have to experience the scenes we have witnessed tonight.
"We have officially requested a formal investigation into the causes of these unacceptable issues."
Football Supporters Europe, a lobby group, said fans were not to blame for the "fiasco" at the Stade de France, while Kelly Cates, the daughter of Liverpool legend Kenny Dalglish, described the pre-match scenes outside the ground as "absolutely shambolic".
There were still large sections of empty seats in the official Liverpool end of the 80,000-capacity stadium at the time the game was supposed to start.
Some 6,800 security forces were deployed for the event, with between 30,000 and 40,000 Liverpool fans without tickets for the final expected in Paris.
A fan zone with a capacity of over 40,000 was set up for them on an avenue in the east of the French capital.
Around 20,000 fans of each club were officially allocated tickets for the game.