Eleven RUC officers were injured and four people arrested after police and loyalist protesters clashed at Drumcree hill late on Saturday night.
The RUC said police officers were attacked by gangs of youths throwing stones and fireworks after an Orange Order "mini-Twelfth" demonstration in Portadown earlier in the evening.
Yesterday, one RUC officer remained in hospital after being struck on the head by a bottle.
However, Mr David Jones, a spokesman for the Orange Order in Portadown, was critical of police actions at Drumcree on Saturday.
He claimed several civilians were injured when police officers in riot gear charged the crowd, tactics he described as "heavy-handed".
Orangeman Mr William Ramsay, who was in Drumcree on Saturday, accused RUC officers of engaging in "provocative behaviour deliberately designed to provoke confrontation".
"The police were singling out individuals before they charged the crowd. They attacked anyone who got in their way.
"It appears that certain elements within the RUC are now deliberately seeking confrontation with protesters at Drumcree. There is no respect for the RUC within loyalism now."
Earlier on Saturday, thousands of Orangemen from across the North had attended four separate rallies in Portadown, part of the local Orange district's mini-Twelfth demonstration.
The centre of Portadown came to a standstill as the Orangemen, headed by Grand Master Robert Saulters, paraded through the streets to rallying points at Corcrain, Drumcree, Park Road and Woodhouse Street.
Thousands of supporters, standing six and seven-deep in places, cheered and applauded as the parade, accompanied by loyalist bands from as far afield as Glasgow, made its way through the town.
Senior Orangemen at each venue read out a statement from the Grand Orange Lodge of Ireland calling for peaceful protests in support of the Portadown Orange District's stance at Drumcree.
The Grand Lodge, the statement continued, stood "shoulder to shoulder" with the Portadown Orangemen.
The statement also said the Grand Orange Lodge remained committed to "finding a just and lasting solution" to Drumcree.
The Orangemen also reaffirmed their support for "the great principles of freedom of movement and freedom of assembly".
Yesterday, the Garvaghy Road Residents' Coalition accused the Portadown Orangemen of deliberately increasing tension in the town in the run up to this year's Drumcree parade.
Residents' spokesman Mr Breandan Mac Cionnaith said Saturday's Orange parade had "effectively sealed off the Garvaghy Road from 6 p.m. onwards".
"We believe that this is just a taste of things to come. The Orange Order has 20 more parades planned for this area between now and July 4th.
"It is further evidence, if that was needed, of the continued intimidation of the nationalist community in Portadown."
Meanwhile, the Moderator of the Presbyterian Church yesterday warned that the implications of the Drumcree dispute could spell disaster for the whole community in the North.
The Rev John Lockington, himself an Orangeman, said both sides in the dispute needed a new approach and readiness to co-operate.
Referring directly to Drumcree, Mr Lockington said: "If the situation continues the implication for the whole community is one of absolute disaster."