Rioting loyalists, some wielding swords, attacked the police in a major outbreak of violence as their anger over a parade ban exploded. Thirty police were injured in the rioting.
July 12th is the traditional marching day when they celebrate King William’s victory at the Battle of the Boyne.
This year, widespread rioting by Loyalist took place in Belfast after they were stopped from marching close to a Catholic area in Ardoyne, North Belfast.
A PSNI spokesman said: "There is an element within these crowds that is intent on violence. Public safety is of paramount concern and individuals if they are gathering to watch events are advised to disperse."
Sinn Féin MLA Gerry Kelly blamed the violence directly on the Orange Order and unionist politicians.
"Speech after speech at the various (Orange) demonstrations were clearly designed to stir up sectarian tension and have alongside the Orange Order's failure to abide by Parades Commission determinations led directly to the violence in Belfast," he said last night.
"No amount of hand-wringing or denial in the coming days from the Orange Order and unionist politicians can alter that reality.
"People had a right to expect better, instead what we got was a very deliberate strategy with the inevitable results being seen on the streets."
As violence escalated the Orange order rescinded an earlier call for opposition to the march being banned but it was too late to prevent much of the violence.
North Belfast DUP MP Nigel Dodds, who had condemned the march ban in increasingly strong language this week, was himself reportedly injured in the disturbances that followed.
Dodds had earlier accused the Northern Ireland Secretary Secretary Theresa Villiers of ‘deliberate deception’ in how she responded to the Parades Commission ban.
The leader of the Orange Order has described the Parades Commission decision to restrict the Orange Order march through the north Belfast nationalist area of the Ardoyne as absurd.
Instead Orange Order Grand Master Edward Stevenson called on Northern Ireland Secretary Theresa Villiers to scrap the Parade Commission rather than the march.
But the commission, which determines where and when parades can march in Northern Ireland, refused to lift the ban that would have seen the Order parade through an area where their presence is seen as an annual provocation.
A recent study found that 70% of the annual parades in Northern Ireland are organised by Protestant or unionist groups. In total 2863 parades were held in 2007 and of these 2270 were loyalist, 144 were nationalist, the study found.
'The absurdity of preventing three Orange Lodges in Ligoniel from partaking in a dignified parade on their return from the Twelfth celebrations, while rewarding those who engage in violence and go out of their way to be offended by our traditions, has surely sounded the death knell for this charade of a commission,' Stevenson told the Belfast Telegraph.
Speaking at a parade in Derry earlier this week Stevenson claimed that republicans were engaged in a cultural war to erode all the symbols of Britishness in Northern Ireland. Stevenson also reportedly noted that the commissions decision followed Belfast City Council's decision last year to restrict the flying of the Union Flag from the City Hall from 365 days to designated days.
But the County Tyrone farmer reserved his fiercest criticism for the Parades Commission, mistrusted by the Orange Order for insisting they not parade though some flashpoint areas.
‘Recent days have also demonstrated the increasing incompetence of the Parades Commission as it continues on its relentless crusade to denigrate Orangeism and the values we hold dear,’ Stevenson said, blasting the independent body that is made up of figures appointed by the Government and led by community work veteran Peter Osborne.
Stevenson added: ‘I call on the Secretary of State to immediately cease offering this unelected quango life support; and finally put it out of its misery - for the good of all in Northern Ireland.’
Nationalists take a different view, often seeing the Parades Commission as the only impartial referee between the two communities over contentious march routes.
The Parades Commission's decision to stop Orangemen marching through Ardoyne on their return from their Belfast gathering was taken in the light of years of serious violence that followed each march.
Local residents claim the annual parade caused major inconvenience, hemming them into their area for hours whilst the police facilitated all the visiting bands and lodges.
Critics have also pointed to the increasingly hardline tone of Dodds and Stevenson in the days before the rioting for goading the political tensions that boiled over last night.