The Security Plan in Lille disintegrated when Police gathered in large numbers and charged fans, writes Sky's Tom Parmenter.
All day the French Riot Police had worked to contain and disperse pockets of trouble in Lille.
At times they worked in tandem with British officers who had been drafted in to help keep the peace. At times it was textbook policing.The trigger for their dramatic change in tactics as the evening wore on was the behaviour of a group of rowdy England fans enjoying themselves at a bar.
:: Riot Police Charge At England Fans In Lille
Almost all of them were English - we'd spoken to some and listened to the familiar songs for an hour or two.
It was boisterous and noisy: one guy decided to get naked and climb up onto a 10ft road sign.
As far as I saw though none of them were being violent or aggressive towards the cops or other fans.
But the French police decided they had had enough.
They assembled in big numbers and then charged in - prompting unseemly running street fights.
Then the CS gas and the pepper spray came out, and the baton charges following police flash bang fireworks.
People did move, they had to, but it also quickly escalated an already tense situation.
This wasn't Marseille - we didn't see the big groups of well organised Russian ultras - but we did see the odd Russian goading and occasionally attacking English fans.
There were other nationalities involved too but it is once again a minority of England fans who the French police will blame.
Their solid security plan that they had worked so hard to implement quickly descended into chaos.
Whoever was to blame - nobody comes out of it well.
Sky News.
