POLICE were attacked by missile-throwing loyalists during fresh violence in Northern Ireland tonight.
Youths attempted to hijack vehicles as a protest by up to 100 people turned violent in south Belfast.
Countless roads have been blocked across the city causing disruption to shoppers and commuters days before Christmas.
Some retailers said their businesses had been devastated by a campaign which has continued since the start of the month, following the reduction in the number of days the Union flag can be flown from Belfast City Hall.
The Police Service of Northern Ireland said there had been demonstrations in Greater Belfast tonight.
Northern Ireland Secretary Theresa Villiers today met leaders of Northern Ireland political parties to discuss the flags controversy.
"I have today urged Northern Ireland's political leaders to come together to find a way forward to resolve the ongoing protests on flags," she said.
"It is vital that all the parties work together to make progress towards a cohesive and shared society where decisions on issues like flags can be made in a way which respects different views and takes into account the different traditions and identities of modern Northern Ireland."
She said she understood the strength of feeling but the disruption caused by these protests was damaging Northern Ireland's economy, particularly for retailers heavily dependent on shoppers in the run-up to Christmas.
"The fact that threats and protests continue to impede elected representatives in carrying out their duties also continues to be a major concern."
She said there was a lot to look forward to in Northern Ireland.
"None of us want to see the clock wound back to an era of sectarian tension when there is such important work to be done to rebalance Northern Ireland's economy and boost jobs and growth."
One police officer has been injured and the force has come under attack from missile throwers in the Lower Newtownards Road, Sandy Row and Shaw's Bridge areas. Several hundred people were involved.
Around 200 people are involved in the disorder on the Newtownards Road.