Media playback is unsupported on your device Media caption Protesters threw bricks and smoke bombs at the police

Northern Ireland's chief constable Matt Baggott has warned that police will "deal firmly" with outbreaks of violence linked to union flag protests.

On Saturday, police came under attack in east Belfast for the third night running.

Since protests began over the decision to fly the union flag at Belfast City Hall only on designated days, 52 police officers have been injured.

Police said they fired plastic bullets three times during Saturday's violence.

Water cannon was also used as officers came under attack from over 100 people, throwing petrol bombs, stones and fireworks. One officer was injured.

Seven of eight people arrested in east Belfast have been charged with riotous behaviour. They appeared at a special sitting of Belfast Magistrates Court on Sunday.

"I want to commend the tireless courage of my officers at this very difficult time," Chief Constable Matt Baggott said.

"You may be assured there will be sufficient resources in the event of more disorder for however long is necessary.

"The police service will continue to do everything possible to maintain law and order and we will deal firmly with outbreaks of violence."

Church leaders, local politicians and community workers met for more than three hours on Sunday to discuss the recent violence

However, Robin Newton, of the Democratic Unionist Party, said a lack of engagement from protest organisers was making it difficult to see an end to the unrest.

"We have to find a way out of this, but how we do it, I don't know," he said.

Police Supt Paula Hillman said officers were being subjected to "sustained, serious, violence".

"They are being attacked with petrol bombs, masonry, and bricks," she said.

"Lasers are also being used against police officers and those in the police helicopter.

"We're sending out a very clear message to people - we respect people's rights to peaceful protest but if you are going to engage in violence, we will robustly apprehend those either by arresting them at the time or as a result of subsequent follow-up investigations and bring those people before the courts."

On Saturday afternoon, a 38-year-old man was arrested on suspicion of attempted murder after shots were reportedly fired at police.

During the day, a protest took place in the city centre over Belfast council's decision to only fly the union flag on designated days.

Up to 1,000 loyalists demonstrated outside Belfast City Hall.

Police said they later dealt with public disorder in a number of locations including Templemore Avenue and the Albertbridge Road.

Bricks, bottles, fireworks and smoke canisters were thrown by the rioters on the Lower Newtownards Road.

Image copyright Reuters Image caption Saturday was the third conscecutive night of trouble in east Belfast

One officer was injured, but did not require hospital treatment.

The chairman of the Police Federation, Terry Spence, said the police were being severely stretched by the disorder and by ongoing dissident republican activity.

"At the time of the inception of the Police Service of Northern Ireland, we had 12,500 full-time officers and we were backed up, at that stage, by 13,000 troops," Mr Spence said.

"Now we have 7,000 full-time officers and there is no military support or back-up and yet the threat level is worse and much more severe than it was 10 years ago.

"That has placed enormous strain and pressure on the officers of the PSNI."

Some loyalists claimed Saturday's trouble was sparked when they were attacked by republicans from the Short Strand area.

Third night

It was the third consecutive night that police have been attacked in Belfast.

Image copyright Pacemaker Image caption A number of vehicles were burnt out during the violence in east Belfast

Nineteen officers have been injured since Thursday and 27 people arrested.

Thirteen people appeared at a special sitting of Belfast Magistrates Court on Saturday night charged in connection with the recent rioting in east Belfast.

Eleven men and one woman were remanded in custody. One woman was released on bail to attend a hospital appointment.

The special two-hour sitting was before Judge George Connor.

A campaign of street demonstrations has been ongoing since Belfast City Council took a vote on 3 December which limited the number of days the union flag is flown at Belfast City Hall.

Since then 70 people have been arrested, 45 of whom have been charged with public order offences.