Police and security services colluded over loyalist killings of six Catholic men gunned down while watching a World Cup football match, a police watchdog has found.

Northern Ireland's Police Ombudsman Dr Michael Maguire has concluded that one suspect in the Ulster Volunteer Force attack on the Heights Bar in Loughinisland, County Down in 1994 was a police informant.

He said that the murder squad that carried out the mass shooting had been involved in a number of other murders in the period beforehand, but had avoided arrest because the Royal Ulster Constabulary's Special Branch intelligence unit had withheld evidence from RUC detectives investigating the crimes.

Dr Maguire said that Special Branch officers had adopted a "hear no evil, speak no evil, see no evil" mind-set that placed the collection of information above the detection and stamping out of crime.