Chaotic and frightening scenes outside the Stade de France in Paris led to the Champions League final kick-off being delayed by more than half an hour.
Supporters have also said that tear gas was used at a fan zone immediately after the final whistle, while others at the game reported being attacked by locals on their way to the train stations at full-time.
Here, the PA news agency looks at what we know and what could happen next.
A large number of Liverpool fans were stuck outside the perimeter of the stadium, in some cases for hours on end, with many missing the kick-off despite arriving well in advance.
Fans reported being crushed as more and more people gathered, and the situation was compounded by French police stationed inside the fence using tear gas on fans.
Gate Y, one of the two main gates which 20,000 supporters were trying to access, was closed for up to an hour in the lead-up to kick-off.
What went wrong?
Supporters who had managed to get inside were told on the big screen that the delay to kick-off was caused by the ‘late arrival’ of fans, although there is clear evidence of supporters gathering well in advance of kick-off.
There were suggestions that organisers did not want to describe the issues as being related to ‘security’ initially to avoid alarming those inside the stadium, but however that first message came to be transmitted, it seems to have been wholly inaccurate.
What have Liverpool said?
The club have called for a formal investigation into the causes of the issues in gaining entry to the stadium, which they described as “unacceptable”.
What about UEFA?
The competition organiser said the turnstiles at the Liverpool end had become blocked by “thousands of fans” who it said “purchased fake tickets which did not work in the turnstiles”.
UEFA said the police had used tear gas in order to disperse the growing numbers building up outside the stadium in the lead up to kick-off.
“UEFA is sympathetic to those affected by these events and will further review these matters urgently together with the French police and authorities, and with the French Football Federation,” its statement concluded.
Have the French authorities commented?
The Paris police prefecture also blamed people either without tickets or with fake tickets who “employed strong force to try to penetrate the perimeter”, causing delays for fans who did have tickets.
“Capitalising on this behaviour, a certain number of people managed to breach the fences protecting the stadium interior,” the police statement continued.
“The rapid intervention of security forces allowed calm to return and helped remove the disruptors from the surroundings of the Stade de France. This dispersal of spectators took place without difficulties.”
The police reported 68 arrests at the city’s fan zones, where Liverpool supporters said tear gas was deployed immediately after the final whistle.
What happens now?
A formal UEFA investigation must surely be commissioned into the events surrounding Saturday night’s chaos, just as one was after the Euro 2020 final at Wembley last summer.