Chief Constable Sir Hugh Orde has hit out at the Orange Order after loyalist gunmen opened fire on his officers during ferocious rioting in Belfast last night.
Dozens of policemen and women were feared injured as blast and petrol bombers went on the rampage across the city and beyond.
Two civilians were also in hospital, one shot and the other caught in an explosion, when street violence erupted over a bitterly-disputed Orange march. Hijacked cars and buses were set alight and used to block roads.
A disused garage also went up in flames and Army explosives experts brought in to defuse seized pipe bombs.
Plastic bullets and water canon were turned on the mobs carrying out relentless attacks on police and soldiers.
Sir Hugh praised the restraint shown by the security forces, instead delivering a damning assessment of the Orange Order appeal for public support over the controversially re-routed Whiterock Parade in west Belfast.
He said: "Police officers and soldiers have come under sustained attack.
"They have been attacked with missiles, petrol bombs, blast bombs, and pipe bombs. They have been shot at.
"The Orange Order must bear substantial responsibility for this. They publicly called people on to the streets. I think if you do that you cannot then abdicate responsibility."
Sir Hugh urged political and community representatives to help his forces end to the disorder which threatened to spill out from Belfast to the surrounding districts of Newtownabbey.
Police confirmed six officers received blast bombs injuries while another six suffered minor wounds during associated trouble at an east Belfast interface. But it was feared that the final injury total would be much higher.
"It's bedlam at the minute and plenty of our boys are just walking wounded," one police source said.
Sniper bullets and bombs struck a number of armoured Land Rovers during some of the worst violence on the West Circular Road.
At one stage officers dived for cover behind their vehicles amid the gunfire. Up to 1,000 loyalists were reported tonight on the streets of the Shankill, where the march had started out.
Shaun Woodward, the Northern Ireland Security Minister, said he was appalled by the violence and criminal behaviour on the streets.
"There can be no justification whatsoever for the disgraceful violence and disorder we have seen," he said.
"The attacks on both police and soldiers, some of whom have been seriously injured, are to be utterly condemned.
"In protecting the community from violence they have paid a heavy price."
Orangemen and their supporters had been incensed by a decision by the ruling Parades Commission to reroute the Whiterock Parade, following opposition from residents. Instead of passing through security gates on to the Springfield Road, marchers were told to go through the site of the former engineering firm, Mackies.
As they made their way through crowds on both sides taunted each other. The gates at Workman Avenue, locked to keep loyalists out, were pounded sporadically.
But as the worst of the violence flared further up the route, police fired baton rounds at rioters. Disturbances then spread to the Upper Crumlin Road/Hesketh Road junction of north Belfast, with security forces pelted by more petrol bombs and stones.
Dozens of vehicles were hijacked and set on fire at police lines, police said. One of the force's water cannon was damaged during the gunfire.
Three more cars were reported on fire on the Ardoyne Road, while a burning bus blocked off North Queen Street, close to the city centre.
Before the march reached the most hotly disputed section, some clashes were reported. Sinn Fein claimed hundreds of loyalists emerged from the Sandy Row district and attacked nationalists on the Grosvenor Road.
Police Land Rovers were brought in to keep the two sides apart and clear the main Westlink motoring route through the city. Disturbances at the Short Strand/Albertbridge Road peaceline in east Belfast also rumbled throughout the day.
Further road blocks took place at Ligoniel and the Crumlin Road in the north, and at the city centre Shaftesbury Square.
Sinn Fein claimed loyalists had dragged Catholics from cars before seizing control.
Party president Gerry Adams also warned of a plot to goad Catholics into retaliatory strikes at the city's peacelines.
He said: "Thus far, due to the discipline of nationalists and republicans, things have remained fairly calm.
"However, there is a concerted attempt under way to draw young nationalists and republicans into conflict at interface areas across Belfast."
The gunfire confirms fears that loyalist paramilitaries planned to take to the streets. Thousands of Protestants had been expected at a major rally in north-west Belfast to protest at the parade ban.
But the Orange Order claimed nationalists attacked their marchers in east and west Belfast and accused police of failing to protect them.
A spokesman claimed when marchers approached the Grosvenor Road only one police vehicle was there and police were powerless to protect them.
He said: "Yesterday, Assistant Chief Constable Duncan McCausland gave repeated assurances to the public via media interviews that he had sufficient manpower and resources to deal with any eventuality that might arise.
"Clearly Mr McCausland is not up to managing the situation and containing nationalists bent on causing trouble. The PSNI's response to these troublemakers is both scandalous and pathetic."
Democratic Unionist Party leader Ian Paisley, who was due to address the rally at Woodvale Park, claimed the security operation stopped Orangemen from attending.
He also criticised the authorities behind the reroute, accusing them of treating marchers shamefully.
The North Antrim MP said: "The Parades Commission are to blame for the mess that has been created. The commission treated elected representatives with contempt by its refusal to even call us to put our case. We were refused the opportunity to give greater detail.
"At this difficult time I am appealing to all law abiding people to remain calm."
Nationalist SDLP representatives issued a strong condemnation of the violence.
West Belfast councillor Tim Attwood said: "We appeal for calm from all sides. The loyalist violence which has erupted is completely wrong and must stop. The loyalists responsible for this trouble are out to raise tensions and cause serious damage."
PA