A police officer at the Trafalgar Square Thatcher protests has been captured on camera telling members of the public that the crowd had been infiltrated by Millwall football fans.
The officer goes on to say that the fans had been causing fights and were throwing bottles - earlier reported to be filled with urine.
Moments later, people are seen throwing bottles at the police and the crowd.
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Another mild day with highs reaching up to 13C degrees in mild southerly winds