Image caption A car was set on fire in north Belfast on the fourth night of trouble

Police have been attacked with blast bombs, a pipe bomb, petrol bombs and masonry during trouble in Northern Ireland on Monday night.

Twenty-seven officers were injured as they dealt with public disorder in east, north, and south Belfast, Newtownabbey and Portadown.

In east Belfast, at least six blast bombs - homemade devices packed with explosives - were thrown at police.

Since Friday, 71 officers have been injured and there have been 60 arrests.

Police said some of the officers injured had suffered heat exhaustion as a result of the warm weather, heavy protective equipment and long shifts.

Speaking in the House of Commons on Tuesday, Secretary of State Theresa Villiers said: "We will not tolerate lawlessness on the streets of Belfast any more than we would tolerate it in any other UK city.

"No stone will be left unturned in building the case for more arrests and more criminal convictions.

"I am confident that for some that will mean that the next 12th of July holiday will be spent not out in the sunshine following the parades, but locked up in prison living with the consequences of their crimes."

She said while the Orange Order's announcement of the suspension of its protest was welcome, it must now call it off completely.

Baton rounds

Of those arrested over four consecutive nights of violence, 32 have been charged.

At about 19:00 BST on Monday, serious trouble began in east Belfast at a sectarian interface on the Newtownards Road.

Officers fired two plastic baton rounds and deployed water cannon after they were attacked with petrol bombs, masonry and other missiles during five hours of sporadic violence in the area.

Some of the blast bombs were thrown from the nearby loyalist Pitt Park area, according to police.

A BBC journalist witnessed golf balls being thrown from the nationalist Short Strand area.

Pipe bomb

Media playback is unsupported on your device Media caption There was trouble in east, south and north Belfast

The fourth night of trouble followed a controversial ruling by the Parades Commission, banning an Orange Order parade from marching past a sectarian flashpoint at Ardoyne, north Belfast on 12 July.

In north Belfast on Monday evening, five officers sustained minor injuries after a pipe bomb was thrown at them on the Crumlin Road.

Police said the device had been thrown from Brompton Park, in the nationalist Ardoyne area, at about 17:00 BST.

The pipe bomb attack took place close to where up to 1,000 people were taking part in a loyalist protest against the parade ruling.

A loyalist march walked to police lines along the Woodvale Road and then joined protesters at Twaddell Avenue. Police instructed that the march was an illegal parade and stopped it from going further.

Hospital treatment

Elsewhere in north Belfast, there was trouble on the New Lodge Road, Woodvale Road and Mount Vernon areas.

Eleven officers were injured when they were hit with masonry during rioting on the New Lodge Road. Two of them required hospital treatment.

One officer was injured by masonry in Mount Vernon after trouble broke out after an earlier loyalist protest on the Shore Road. A car was hijacked and set on fire, as police cam under attack from petrol bombs and other missiles.

In the south of the city, rival groups gathered close to Broadway and Glenmachan Street and a crowd of about 50 people threw stones at each other and the police.

Petrol bombs were also thrown at North Queen Street, where a car was set on fire.

Police said they had liaised with community representatives in north Belfast "in an effort to restore calm".

Sectarian rioting

In Portadown, nine officers were injured when they were hit with masonry, and two of them were taken to hospital.

They were hurt during sectarian rioting in Corcrain Road, Charles Street and Park Road in the County Armagh town.

A PSNI spokesman said officers were attacked by both sides, as fireworks, bottles and golf balls were thrown from opposing crowds.

In County Tyrone, the A4 dual carriageway was closed during the early hours of Tuesday morning because a number of tyres had been set on fire.

Traffic was diverted through Moygashel for several hours but the road has since reopened.

Police in Londonderry dealt with a number of white line protests on the Glendermott and Limavady roads in the Waterside area on Monday night.

Up to 90 people were involved in the protests, which took place from about 19:00 to 20:30 BST. They passed off without incident.

During this period, police seized about 20 paint bombs in the city, believed to have been stashed by local youths.

'Deplorable'

Police Service of Northern Ireland Superintendent Emma Bond, speaking about the pipe bomb in north Belfast, said: "We consider ourselves extremely fortunate that we are not dealing with a much more serious incident and that all of the officers were able to walk away from that situation unharmed.

"We have appealed for calm in the area and I continue to do so.

"I would appeal to anyone with influence in the community to exert it to ensure that the next few days pass off without incident."

DUP assembly member William Humphrey said loyalist protesters had been demonstrating peacefully in the Twaddell Avenue area when the incident happened.

He described the attack as an "attempt to injure and kill".

Sinn Féin assembly member Gerry Kelly said the attack was "completely unacceptable" and "not supported by the vast majority of the community in Ardoyne".

Image caption Petrol bombs were thrown at police in east Belfast

It emerged on Monday night that US Vice-President Joe Biden had expressed "deep concern at parade-related violence and attacks on police" in conversation with the Northern Ireland First Minister Peter Robinson and the Deputy First Minister Martin McGuinness.