In his annual report Sir Ronnie Flanagan said: "Sadly some have shown an eagerness to use this terrible crime to mount an attack upon the integrity of the RUC.

"This will not be allowed to undermine the rigorous and professionalism with which the (Rosemary Nelson) investigation will be conducted."

Referring to the fact that the investigation is being led by an English officer, Mr Flanagan said: "I am indebted to Colin Port, deputy chief constable of Norfolk Constabulary, who is in overall command of the investigation and to the Federal Bureau for investigation for their assistance."

The future of the RUC is under review

However, Mr Flanagan said he recognised the importance of "enabling people to have their say in determining our future direction" through bodies like the Patton Commission on Policing set up under the Good Friday Agreement.

Sir Ronnie said the conflicting desire to parade and protest has drained police resources and led to tragic consequences.

He said: "The violence which has been allowed to become associated with deeply held beliefs on the parading issue has led to tragic consequences, not least for the family and friends of a young policeman (Frankie O'Reilly) who gave his spare time to coaching youngsters in football."

Out of 3,472 parades last year, public disorder occurred at 25, he said.

Need for partnership

Mr Flanagan appealed to the Northern Ireland public to become more involved in "collaborative working partnerships between us and all communities".

He said: "Policing in partnership with the community is central to all we seek to achieve."

Mr Flanagan pledged that the RUC would remain vigilant to the continuing terrorist threat and said the force would pursue lawbreakers with the utmost vigour.

He said the year under review had seen continuing attempts at political development against a background of cessations of "military activities" by the major paramilitary organisations on each side of the divide.

Omagh 'obscenity'

However, "totally abhorrent" paramilitary-style attacks had continued, he said.

Sir Ronnie said 62% of the attacks had been attributed to loyalist groups and the remainder to republicans.

He said: "The staggering obscenity of the Omagh bombing, together with continuing highly dangerous pipebomb and grenade attacks, reminds us that there are republicans and loyalists who remain determined to carry on with the old failed ways of murder, maiming and mayhem."