Deputy First Minister Martin McGuinness branded the Orange Order a "disgrace" after at least 20 police officers and a number of civilians were hurt when serious rioting erupted across Belfast.
Twelfth celebrations were marred by sustained violence which saw North Belfast MP Nigel Dodds among those injured.
The trouble erupted in the wake of a decision to halt the return of a Twelfth parade past the Ardoyne flashpoint.
One man was arrested for disorderly behaviour and another for provocative behaviour.
A woman who said she was hit with a plastic bullet said: "I am just shocked, to be honest. I was just standing here doing nothing. We were told were were allowed to stand here until 8pm."
A friend of the woman claimed that at 7.49pm, police deployed the water cannon and targeted them with plastic bullets.
Deputy First Minister Martin McGuinness last night tweeted: "Responsibility for tonight's violent attacks on police and the community rests with the leadership of the Orange Order, they are a disgrace."
SDLP MLA Conall McDevitt also tweeted: "We need to hear the leaders of unionism and loyal orders call the people off the streets."
First Minister Peter Robinson last night appealed for calm and blamed the Parades Commission.
He said: "Violence and attacks on the PSNI and wider community are wrong, can never be justified and must stop. While there is justifiable anger and frustration at the Parades Commission, who bear much responsibility for the situation in Belfast, as do those who attacked parades as they passed certain locations, nonetheless, those who are using the cover of protest to attack the police are massively damaging the cause they support.
"Violence is undermining a just cause and runs totally against the wishes of the Orange Order for protest to be entirely peaceful.
"My thoughts are with those who have been injured this evening, including my colleague Nigel Dodds MP and other Orange Order members, police officers and civilians. I appeal for cool heads to prevail at this time."
The Grand Orange Lodge of Ireland last night called for an end to the violence.
Mr Dodds was taken to hospital in an ambulance after he was hit on the head with a missile which had been thrown at police lines by a loyalist rioter.
In east Belfast, serious trouble broke out around 8pm at St Matthew's Church near the Newtownards Road. One police officer and a number of people were injured when bottles, bricks and fireworks were thrown at police in riot gear and towards the church.
Loyalist rioters also let the air out of police Land Rover tyres.
Earlier in the evening, missiles were thrown from and towards the nationalist Short Strand. Police closed the Lower Newtownards Road to motorists around 8.45pm and deployed two water cannon as they tried to move groups of protesters away.
The Albertbridge Road and Castlereagh Street were also closed shortly after 10pm. Ball-bearings were fired and there were two arrests.
There were minor scuffles near York Street. Nationalists ran towards bandsmen and threw police cones. Calm was restored after the PSNI formed a barrier.