Police were heard to tell anti-Thatcher protesters in Trafalgar Square that Millwall football fans had joined the demonstration and were "throwing bottles of urine" at officers.
Millwall supporters were earlier involved in crowd trouble during the club's FA Cup semi-final against Wigan at Wembley.
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Almost 80 new cases were recorded on Wednesday.
The First Minister could decide on Thursday to move the country on to phase one of its four-part plan to relax the rules.
Several papers keep the pressure on the Government over the Dominic Cummings saga, while some are starting to move on.