Rival protesters clashed outside the Palace of Westminster today, as BNP supporters and anti-fascist campaigners came to blows.
At least one man, a BNP activist, suffered a large cut to the nose after fierce shouting from either side of gated barriers spilled into violence.
Dozens of police sought to break up the disorder, at around 1pm today, after the chanting escalated.
BNP and anti-fascist protesters clash outside Parliament during demonstrations today
Events have also been planned in various locations across the country by the English Defence League
Dozens of police were required to break up the disorder this afternoon.
Police sniffer dogs were also deployed to help calm the situation, as tempers flared.
The fighting came despite calls for peace from police and the family of soldier Lee Rigby in the wake of his death.
The 25-year-old's family yesterday stressed that the young soldier would not have wanted violent attacks to be carried out in his name, and urged protesters to remain peaceful.
The BNP had planned to march from Woolwich Barracks, but were banned from doing so by Scotland Yard, amid community fears that their presence could prompt disorder.
Around 100 people gathered on Old Palace Yard, clutching BNP banners and calling for 'hate preachers out'.
A short time later, counter protesters began directing chants at them, calling them 'fascist scum', 'you racist Nazis'.
At least one man suffered a large cut to his nose after fierce shouting spilled into violence during the demonstration today
Around 100 people gathered on Old Palace Yard, clutching BNP banners and calling for 'hate preachers out'
Dozens of police sought to break up the disorder this afternoon after the chanting escalated
BNP leader Nick Griffin arrives to address the party at the demonstration outside Parliament
The British National Party seen demonstrating in the Palace of Westminster in Whitehall, London
The BNP had planned to march from Woolwich Barracks, but were banned from doing so by Scotland Yard, amid community fears that their presence could prompt disorder
Scotland Yard said that a group, believed to be part of the Unite Against Fascism (UAF) protest, gathered in a pre-arranged penned area - but some were unwilling to remain within that area.
A spokesman added: 'Due to police concerns about serious disruption to the life of the community, and the potential for serious disorder should this counter protest confront the BNP organised protest, police have imposed conditions under Section 14 of the Public Order Act.
'Those conditions state that the protest must take place in Whitehall Gardens junction with Whitehall.
'A group of about 300, also believed to be part of the UAF protest, were stopped in Old Palace Yard junction with Abdingdon Street Street.
'This group have now been notified of the conditions imposed under Section 14 and requested to move to Whitehall Gardens to continue their protest. Officers are in negotiation with this group.'
Police sniffer dogs were also deployed at the demonstration to help calm the situation, as tempers flared
The violence came after despite calls for peace from police and the family of soldier Lee Rigby in the wake of his death
The clashes came after BNP supporters and anti-fascist campaigners held opposing demonstrations today.
The crowd of anti-fascist protesters heavily outnumbered the BNP supporters. They held banners which read 'smash the BNP' and 'say no to Islamaphobia'.
Around 50 of them were reported to have rushed towards one man as he was escorted by police to the area containing the BNP group.
BNP leader Nick Griffin was attended the protest. He said the murder of soldier Lee Rigby would not be an isolated incident.
Police have said 20 arrests had been made from the Unite Against Facism protest by this afternoon.
Events have also been planned in various locations across the country by the English Defence League.
Members were urged to avoid racist or 'Nazi actions' during the marches today.
Twitter user @Official_EDL retweeted a post which read: 'Everyone at #WalkForLee today, no chanting and no racise/nazi actions, leave the booze til after, don't hijack our movement and ruin it. (sic)'
English Defence League demonstrations have been taking place across the country, including this march in Leeds
Anti-fascist campaigners were also present in Leeds as the EDL held their march
EDL members were urged not to chant and not to make 'racist/nazi actions (sic)' during planned protests today
Far-right group EDL leader Tommy Robinson carries a floral tribute to Drummer Lee Rigby in Luton today
A group of anti-EDL protesters march to the city of Oxford today to denounce EDL's wreath laying as exploitation.
Meanwhile, rival protests by the Scottish Defence League (SDL) and anti-racism campaigners took place in Edinburgh's Old Town.
The SDL held a static protest outside the Scottish Parliament, while Unite Against Fascism (UAF) organised its own counter-protest.
Police, who were at the scene in large numbers, kept the two groups apart with barriers in the city's Horse Wynd, in front of the Palace of Holyroodhouse.
The road was closed to traffic for the duration of the protest, in which both sides held banners aloft and chanted slogans.
The demonstrations appeared to disperse without any clashes between the two groups.
A demonstration by the Scottish Defence League outside the Scottish Parliament in Edinburgh
The SDL held a static protest outside the Scottish Parliament, while Unite Against Fascism organised its own counter-protest
A Union flag is flown during a demonstration by the Scottish Defence League.
In a statement released through the Ministry of Defence, members of Drummer Rigby's family including his mother Lyn, stepfather Ian, wife Rebecca and son Jack, yesterday said: 'We would like to emphasise that Lee would not want people to use his name as an excuse to carry out attacks against others.
'We would not wish any other families to go through this harrowing experience and appeal to everyone to keep calm and show their respect in a peaceful manner.'
Labour leader Ed Miliband today joined celebrities and thousands of others in signing a letter to a newspaper in protest at far-right groups using the death of Drummer Rigby for their own agenda.
In the letter to the editor of the Daily Mirror, they wrote: 'The EDL and Islamic extremists are more similar to each other than to us. They share a violent, hate-fuelled desire for conflict and war, and we will not let either group tear our country apart.
'We condemn the shameful rise in anti-Muslim violence since Drummer Rigby's killing. The fair-minded majority of Britons understand that a community cannot be blamed for the actions of just two. We know that the EDL does not speak for all Britain, just as we know that Muslim extremists do not speak for all Muslims.'
The former Archbishop of Southwark Kevin McDonald and Imam Ali of the British Armed Forces lay a wreath (left) in memory of Drummer Lee Rigby with other religious leaders and MP's, Woolwich Barracks yesterday
Lee Rigby's family stressed the young soldier would not have wanted violent attacks to be carried out in his name, and urged protesters to remain peaceful.
The letter was signed by stars including Eddie Izzard, union bosses including TUC general secretary Frances O'Grady, politicians and leaders of Islamic, Jewish and Christian organisations.
Yesterday hundreds of people visited Greenwich Islamic Centre, also known as Woolwich Mosque, after Friday prayers for tea and biscuits in an event aimed at calming tensions.
Representatives of Christian, Muslim, Sikh and Jewish communities also placed flowers arranged to spell the word Peace amongst the thousands of bouquets, cards, poems and candles left in memory of Drummer Rigby near the scene of his killing.
'We would like to emphasise that Lee would not want people to use his name as an excuse to carry out attacks against others'
- Family of Drummer Lee Rigby
One of Drummer Rigby's suspected killers who was shot by police was released from hospital yesterday and taken into custody.
Michael Adebolajo, 28, had already been arrested on suspicion of Drummer Rigby's murder, and yesterday was further arrested on suspicion of the attempted murder of a police officer.
Michael Adebowale, 22, has already been charged with murdering the young soldier and is due to appear at the Old Bailey on Monday.
Two men aged 42 and 46 arrested on suspicion of being involved in the illegal supply of guns were bailed today to return to a south London police station later this month.
Meanwhile officers in Scotland last night said a 25-year-old man had been charged in Inverness in connection with an alleged hate crime on an internet memorial page for Drummer Rigby.
In a statement, police in Scotland said a man was charged 'in connection with an enquiry into alleged hate crime comments on Facebook'.
The man is expected to appear at Inverness Sheriff Court on Monday.