The IRA and the UVF are orchestrating street violence in Belfast, according to the PSNI's most senior officer in the city.
Mr Alan McQuillan, an assistant chief constable, said it was clear to the police service that the street trouble in the Short Strand area since the spring is being orchestrated by paramilitary groups on both sides.
"We have two paramilitary groups, one on each side, who are orchestrating this in their respective communities and attacking the other community for their own purposes. So we have paramilitary organisations on both sides basically pursuing a war by other means - street violence."
Mr McQuillan identified the groups: "On the loyalist side it is quite clear to us that the Ulster Volunteer Force is organising this violence and on the nationalist side the IRA is organising this violence."
He said police tactics would change to deal with the trouble, but he would not elaborate. It is known that extra police officers will be deployed to act as a buffer between the two sides.
Meanwhile, 16 British soldiers were injured in renewed sectarian clashes in east Belfast early yesterday.
The trouble flared late on Wednesday evening and lasted into the early hours of yesterday in the Short Strand-Cluan Place area off the lower Newtownards Road.
Stones, petrol bombs, fireworks and pipe bombs were thrown and security sources say soldiers replied with 17 plastic bullets.
The trouble continues to feed into the wider situation, with the Church of Ireland primate appealing for a breathing space to enable politicians to gain the upper hand.
"Blame and counter-blame will achieve nothing," said Dr Robin Eames. "It is surely in the interests of all out communities that we draw back to create a situation in which common sense replaces anger."
Sinn Féin denounced the assistant chief constable's claims. Ms Michelle Gildernew, the Fermanagh-South Tyrone MP, said Mr McQuillan "was the public face of the securocrats within the PSNI who are opposed to the peace process, opposed to the Good Friday agreement and opposed to the political institutions".
The DUP's Mr Sammy Wilson said: "The government must impose sanctions on IRA/Sinn Féin in light of the gun and bomb attacks launched from the Short Strand by the IRA."
The Deputy First Minister, Mr Mark Durkan, asked how Sinn Féin could sustain what he called a propaganda offensive against the police while hinting that it could take up its seats on the Policing Board if legislative reforms are introduced by the British government.
Mr Durkan said yesterday: "The issues that Sinn Féin have been using in a propaganda war against the SDLP, things like plastic bullets, Special Branch, police performance in interface areas - that they have been using to crucify the SDLP for being on the Policing Board - will not stand in the way of Sinn Féin going on the board."