Seven police officers were hurt Saturday night in the violence that began Friday in reaction to the ban on the parade by the Orange Order, a Protestant fraternal organization based in Belfast, The (London) Guardian reported Sunday.
An officer was hit on the head with a piece of masonry and a Belfast press photographer was hit in the face with a brick, the PSNI said.
Close to 1,000 police from England, Wales and Scotland are helping the PSNI, police said. M
Nigel Dodds, the Democratic Unionist MP for North Belfast who was knocked unconscious Friday after a missile thrown toward police hit him on the head, is recuperating at home, his wife said.
"Officers were attacked by petrol bombs, fireworks, masonry, laser pens, and by a whole range of weapons and missiles," a PSNI spokesman said, adding that none of the injured went to the hospital and all stayed on duty.
Since Friday, more than 30 arrests had been made, the PSNI said.
Police said they hope to make more arrests in the coming days based on identifiable faces among the attackers that appear in video footage taken from a police helicopter during the fray.
Northern Ireland Secretary Theresa Villiers said, "The violence last night and the night before was shameful and it is vital that calls for calm are heeded by those responsible for this violence. They say they are trying to defend their culture but they are not defending anything by throwing petrol bombs at police officers."