The police say "sinister elements" were behind last night's sustained rioting in east Belfast.
A crowd of about 200 nationalist youths fought running battles with the police and loyalists after a Sinn Fein rally to mark the closing down of the Short Strand police station.
East Belfast area commander of the PSNI, John McKeag defended his decision to fire six plastic bullets at the rioters.
"I was a senior officer in charge last night and it was my judgement.
"What that means is that I was given an update on what was happening on the ground throughout the whole period and there was significant risk of injury to police officers and the general community.
"It was proportionate, justified and necessary in the circumstances.
"If you look at the bricks that were being used and the ferocity that was being used against officers and the community, then I believe it was totally justified", he said.