The British government has acknowledged that the report on the Loughinisland murders reaches very grave conclusions about police conduct and that it takes allegations of wrongdoing very seriously.
A statement said: “Where there is evidence it should be pursued and those responsible held accountable. Everyone is subject to the rule of law.”
Minister for Foreign Affairs Charlie Flanagan said the “disturbing” report “causes deep concerns” and the findings must be examined with a view to “further investigations and possible prosecutions”.
“The Police Ombudsman’s report is another stark reminder of the need to agree mechanisms for dealing with the painful legacy of the past in Northern Ireland,” he said.
“This is a priority for me in my engagement with the British government and the parties in Northern Ireland.”
Appalling
PSNI Chief Constable George Hamilton said he accepted the report's findings, saying it made for "uncomfortable reading", particularly in relation to the alleged actions of police officers and that they should be "held accountable".
“The ombudsman has stated that collusion was a feature of these murders in that there were both wilful and passive acts carried out by police officers,” Mr Hamilton said.
“This is totally unacceptable and those responsible should be held accountable.”
He also said the murders were “appalling” and that he was conscious of the “hurt and anger” felt by bereaved families and those injured on the day.
“The PSNI remains firmly committed to apprehending those responsible for these murders and appeal to the community for information to allow us to do so.”
Patrick Corrigan, Northern Ireland programme director of Amnesty International, said the latest revelations of collusion by the RUC with loyalist paramilitaries were "deeply disturbing".
“The ombudsman’s inclusive approach to the definition of ‘collusion’, which other inquiries have in the past sought to narrow, helps open the road to proper accountability,” he said.
“As many football fans prepare for Euro 2016, the sad reminder of the bloodshed in Loughinisland during the 1994 World Cup should serve to ensure that there is no further delay in agreeing human rights-compliant mechanisms to investigate all outstanding deaths from the Troubles era.”