Protestant youths in Northern Ireland threw petrol bombs at homes and a church in a Catholic area on Monday night (Tuesday, NZ time) as the latest outbreak of violence in Belfast took on increasing sectarian overtones.
At least one police officer was injured during violent clashes between pro-British and Irish crowds who threw rocks and other missiles at each other, police said in a statement.
The unrest has been some of the most sustained violence in the British-controlled province since a peace deal signed 15 years ago ended 30 years of conflict between Catholic Irish nationalists seeking union with Ireland and Protestant loyalists determined to remain part of the United Kingdom.
Loyalists have held nightly protests since nationalist councillors voted last month to end a century-old tradition of flying the British union flag every day over Belfast City Hall, exposing a deep vein of discontent with the peace deal.
Over the last six weeks, loyalist youths have fought street battles with police on an almost nightly basis that have left over 100 officers injured and raised sectarian tensions.
In the latest rioting, loyalists threw petrol bombs and stones at police, who responded with water cannon, police said.
A bus driver was also injured when youths hijacked two buses in the traditional flash point area within a couple of kilometres of the city centre.
Pro-British and Irish groups clashed on Saturday after mainly Protestant protesters passed the Catholic area on their way home from a rally in central Belfast against the flag's removal.
Politicians have branded rioters the enemies of democracy and claimed they were being exploited by paramilitary groups seeking to wreck the peace process.
The current wave of violence has knocked the city's fledgling reputation and hit the pockets of retailers facing a 30 percent drop in trade over the last two months.