The BBC's Mark Devenport reports on a night of violence

Up to 1,000 Protestant Orangemen gathered at Drumcree, County Armagh, where police had bricks and fireworks thrown at them.

Police, none of whom were seriously injured, retaliated with one plastic bullet.

Four protesters were treated for minor injuries. There were no arrests.

The BBC's Maggie Swarbrick: Ian Paisley arrived to give a rousing speech to the crowd

Orange Order spokesman David Jones blamed the police for the violence.

He said: "It was a totally unprovoked attack by the police who over-reacted to a peaceful protest."

RUC Inspector Stephen Day: The crowd were quite aggressive

Police denied the claims and showed reporters an array protesters' weapons including clubs and pick-axe handles.

Reverend Ian Paisley, leader of the hardline Democratic Unionist Party, later gave a rallying speech to the protesters.

Orangemen have been staging a token round-the-clock protest at Drumcree since they were banned from marching down the mainly-Catholic Garvaghy Road in nearby Portadown, in July.

The violence in July has left an unresolved, bitter legacy

The Parades Commission had banned the Orange Order from following its traditional marching route along the Garvaghy Road in the hope of averting the annual disruption and sectarian aggravation.

A stand-off between protesters and security forces in July culminated with the deaths of three children in an arson attack by loyalists in Ballymoney in County Antrim.

BBC Ireland Correspondent Mark Devenport: It is hard to see a resolution to the problem

The Orangemen have pledged to stay at Drumcree until they get their way and are threatening to stage a major demonstration in Portadown on 19 December.

BBC Ireland Correspondent Mark Devenport said that there had neen no direct negotiations between the Orange Order and the residents of the Garvaghy Road over the march because the local councillor for the area had an IRA background.

He said: "Without those negotiations it is hard to see a resolution."

The latest Drumcree disturbances came as efforts by UK and Irish leaders to breathe new life into the Northern Ireland peace process hit new obstacles.

Bitter row

UK Prime Minister Tony Blair and his Irish counterpart Bertie Ahern expressed their frustration as the talks in Belfast ran into further trouble on Thursday.

David Jones: We do not want any trouble

Agreement on the key structures of the new Northern Ireland Assembly was put on hold after a bitter row between unionists and nationalists.

Mr Blair and Mr Ahern were hoping a deal could be struck ahead of next week's Nobel peace prize presentation to Ulster Unionist Party leader and Northern Ireland First Minister David Trimble and John Hume, leader of the nationalist SDLP.

Mr Blair had flown to Ulster on Wednesday to make a personal attempt to push the talks forward.

Mr Ahern indicated that the February deadline for having cross-Irish border bodies in place could now be at risk.