The proportion of Protestants in Northern Ireland has fallen below 50% for the first time, new census figures show.

The findings follow scenes of violence in Belfast over a ruling to remove the Union Flag from permanent display at city hall.

The Protestant share of the population has fallen from 53% 10 years ago while the proportion of Catholics increased to 45% from 44%.

Demographers predict Catholics, who are younger and have higher birth rates, could become a majority of voters within a generation.

The loss of control of Belfast City Council by Unionist parties last year allowed nationalist parties this month to secure a motion to restrict the flying of the British flag at the city hall for the first time in a century.

The vote has triggered the most widespread loyalist street violence for years, with at least 32 police officers injured and 38 arrests made in eight days.

On Monday, a petrol bomb was thrown into a car as a policewoman sat inside, with the attack being treated as attempted murder by police.

Prime Minister David Cameron is under increasing pressure over his failure to meet Northern Ireland's justice minister following more than a week of violence on the streets.

David Ford, an Alliance Party MLA, said the Prime Minister had yet to return his phone calls from Monday.

In the Commons yesterday Northern Ireland Secretary Theresa Villiers said: "I have been keeping the Prime Minister fully informed on this. He is following events very closely."