Far-right group the English Defence League was involved in fights with 'young Muslims' outside West London Magistrates Court in Hammersmith on Wednesday afternoon, prompting police to make five arrests.
Up to 150 members of the EDL descended on the area to show support for its founder, Stephen Lennon - also known by the pseudonym Tommy Robinson - who was in court charged with a public order offence during Armistice Day in Kensington last year, when Muslim extremists burned poppies. .
A police source said more than 100 officers were drafted in to break up clashes between EDL supporters and Muslim students from nearby Ealing, Hammersmith and West London College.
The EDL claims the clashes were started by members of Muslims Against Crusades. A female EDL is alleged to have been taken to hospital with a facial injury.
The police source added people involved in the fights tried to storm the court, which had to be locked-down and suspended to prevent thugs getting in.
There were also reports of disorder in nearby Margavine Cemetery in Baron's Court.
A police helicopter hovered overhead for about an hour, as people were ushered out of the area.
A Met spokesman confirmed: "Police were called at 4.40pm to reports of disturbances in the vicinity of West London Magistrates Court.
"Officers attended to deal with two groups fighting. Five people have been arrested for various public order offences."
The EDL, which has a history of being involved in demonstrations which descend into violence and end in multiple arrests, insists it was the innocent party in the fights.
In an email to the Chronicle from a woman claiming to be Lennon's PA, Hel Gower, she says the EDL were protesting peacefully when one of its female members was attacked.
"The Police stood there and allowed the Muslims to go among the EDL members, when it was quite clear from their demeanour they were intent on causing trouble, in which they succeeded," she wrote.
The EDL opposes what it sees as the spread of Sharia Law and Islam extremism in England.
It has been banned from marching in the past due to its threat to public safety and is being investigated by police.
Commentators have described the group as being "a dangerous cocktail of football hooligans, far-right activists and pub racists".
The EDL insists it is not racist.
Lennon was later fined by JPs.