Political authorities appealed for calm with Sinn Fein blaming scores of masked gunmen for launching coordinated attacks on the region, British media reported.
Sinn Fein said the men were wearing camouflage clothing and surgical gloves at the second night of violence at the notorious peace wall.
Ulster Unionist Michael Copeland said he believed the violence followed attacks on Protestant-owned homes, but representatives from both sides called for an end to the rioting.
Belfast mayor Niall O Donnghaile, a councillor based in the Short Strand area, said a number of nationalist residents had been injured, including one man knocked unconscious when he was hit on the head with a brick.
“There is no doubt that this was unprovoked and was a carefully orchestrated and planned attack on the area”, said O Donnghaile.
“Homes have been attacked with petrol bombs and paint bombs, bricks, golf balls. I saw what happened”, he added.
He claimed loyalist attacks had sparked violence from the republican side of the divide.
But Copeland said: “I would say it was several hundred involved in very serious, almost hand-to-hand fighting.
“You will always get two sides to these stories. My understanding is that homes on the Newtownards road have been attacked”, added Copeland.
“To be honest it doesn’t really matter who is responsible at this stage, it’s getting it stopped appears to be the problem,” he said.
Meanwhile, in north Belfast, violent clashes marred the first contentious parade of Northern Ireland’s marching season.
Bricks and bottles were thrown at police in north Belfast as the Tour of the North turned ugly when two feeder parades were re-routed from the interface area in Ardoyne