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.
More top news
It is not clear yet whether there were any injuries during the crash near Lockhart, Texas.
The author of the beloved children's books series said it felt 'wonderful' to launch the stage play on the West End
Thousands of people marched in support of Scottish independence supporters marched through Glasgow.