Collusion between police and loyalist paramilitaries was a “significant feature” of the Loughinisland murders in 1994, according to a report by the Police Ombudsman.

The newly-published 160-page report says that there have been “many within the RUC and the PSNI who worked tirelessly to bring those responsible for the Loughinisland attack to justice”.

However, it expresses concern about the approach of some police officers to informants, the information such people were providing, and how the police were choosing to use such information.

Six people were killed and five wounded in the 1994 shootings.

An earlier report by former police ombudsman Al Hutchinson was published in 2011 and later quashed by the High Court in 2012.

The Police Ombudsman, Dr Michael Maguire, said: “The failure to bring the killers to justice cannot be explained solely by the problems with the investigation.

“This report has evidenced many examples of failures to pass on intelligence to detectives engaged in the investigation of serious crime. Investigative lines of inquiry were not followed and individuals who might have been subject to detailed and robust investigation were effectively excluded from such consideration.

“These represent more than ‘intelligence failures.’ At best they are indicative of an ‘intelligence mindset’ which placed the collection of information before the prevention and detection of crime.”

He added: “Many of the individual issues I have identified in this report, including the protection of informants through wilful acts and the passive turning a blind eye; fundamental failures in the initial police investigation and the destruction of police records, are in themselves evidence of collusion as defined by Justice Smithwick.

“When viewed collectively, I have no hesitation in saying collusion was a significant feature of the Loughinisland murders.”