A 17-year old boy has been charged with rioting in connection with trouble which broke out in the east of the city on Monday night.
Crowds attacked police responding to reports that petrol bombs had been thrown at a Catholic church in the nationalist Short Strand area.
A police officer was injured and water cannon was used as stones and petrol bombs were thrown.
A bus driver was also injured during an attempted hijacking and stones were thrown at another bus on the Newtownards Road.
Two men, aged 28 and 69, arrested in connection with separate disorder following a street protest on Great Victoria Street have been released on bail.
A 16-year-old boy was also arrested in Ballymena following a protest in the Larne Road Link area.
He is due to appear before Ballymena Youth Court on Tuesday, charged with offences including disorderly behaviour and obstructing traffic.
Around 100 police officers have been hurt since the start of the flag dispute last month, while over 110 people have been arrested.
It comes after Belfast councillors voted at the start of December to restrict the flying of the Union flag over City Hall to 18 designated days.