The two men who were shot dead by gardaí during an attempted post office raid in north Dublin this morning have been named as Colm Griffin (33) and Eric Hopkins (24), both from Dublin.
Meanwhile, the human rights body Amnesty International has called for an "independent and transparent" investigation to be held into the events "both in the interests of the Garda and in the interests of public confidence and accountability".
A spokeswoman for Amnesty International in Ireland said that in other jurisdictions such cases are automatically referred to an independent investigative body such as an ombudsman "and we still do not have such an office in this State".
Gardaí are carrying out forensic tests to "definitively establish" whether or not a loaded firearm recovered from the scene of the attempted robbery in north Dublin this morning was fired by one of the raiders.
The men were part of a gang trying to rob the post office in Lusk just after it opened at 8am, gardaí said. They were shot by gardaí after they reportedly refused to put down their weapons.
The scene of this morning's incident in Lusk, Co Dublin Photograph: Alan Betson
It is believed gardaí, including members of the Emergency Response Unit (ERU), were lying in wait for the gang overnight. A witness said armed officers were seen exiting a camper van as the raid commenced. Other officers were waiting inside the post office behind the counter when the gang burst in, armed with at least one gun and a sledgehammer.
A Garda statement said: "Armed gardaí challenged five men inside the premises as they were attempting to carry out a robbery shortly after it opened for business at 8am."
"Shots were fired and two men were injured," he added. One man was dead on arrival at Beaumont Hospital while the other died at about 11am in hospital.
Three men and one woman have been arrested in connection with the incident and are currently being detained under Section 30 of the Offences Against the State Act at Coolock, Clontarf, Blanchardstown and Swords Garda stations.
Construction worker Paul Harmon, who was on his way to work, arrived at the post office during the operation.
"As soon as we pulled up, a police car pulled up in front of us and did a handbrake turn to block our way," he said. "As soon as that happened all the police got out of their cars, there were a lot of guns involved.
"Next of all we just heard 'go, go, go, there's somebody on the roof' and then the police officers were running, some of them were running in.
"We had to reverse because a police car was going through past us with a police officer hanging out the window with a gun."
Acting Garda Commisioner, Deputy Commissioner Fachtna Murphy, has appointed Chief Superintendent Kevin Ludlow, Cork City Division, to investigate "all aspects surrounding this incident", the statement said.
In an additional statement this evening, the Garda Press Office said gardaí were conducting an ongoing operation in the area at the time of the attempted armed robbery - "one of a number of such operations which Garda engage in on a regular basis".
The Garda said the scene continues to be cordoned off and a full technical and forensic examination is being conducted by Gardai from the Crime Scene Investigation Unit, Garda Technical Bureau.
"An Garda Siochana regrets the loss of life in any circumstances and conveys its condolences to the families of those who have died.
"The Garda Commissioner recognises the dangers faced by members of An Garda Síochána in the execution of their duty on a daily basis, particularly when confronting armed criminals, and expresses his appreciation to the gardaí involved in this operation in preventing the commission of a serious criminal act."
Additional reporting: PA