The Garda Síochána Ombudsman Commission is appealing for help from potential witnesses to a fatal shooting it is investigating.
GSOC said the "incident involved the discharge of an official firearm in Clonee" that fatally injured a man in Dublin yesterday.
Gardaí had been called to the scene following reports of a man armed with a knife at a Eurospar shop in Hartstown.
The man, named as George Nkencho, had reportedly threatened staff at the shop at around 12.15pm.
Mr Nkencho, who was in his late 20s, then fled from the shop, threatening uniformed gardaí with a knife as he made his way home a short distance away at Manorfields Drive.
Around a dozen gardaí were present at the scene, including members of the Armed Support Unit, and gardaí say they were also threatened with a knife.
They implemented what gardaí call a graduated policing response.
This is where the use of less-than-lethal force options are initially administered in an effort to resolve an incident.
Gardaí say the less-than-lethal use of force options were unsuccessful, and a number of shots were fired from an official garda firearm at around 12.35pm.
Mr Nkencho was treated at the scene by Armed Support Unit paramedics and Dublin Fire Brigade paramedics.
He was transferred to Connolly Hospital in Blanchardstown where he has pronounced dead yesterday afternoon.
A post-mortem examination is due to take place today.
GSOC said it would like to hear from any potential witnesses that may have captured the incident on CCTV, dash-cams or mobile footage.
Anyone with information is asked to contact GSOC at 1890 600 800 or by email at info@gsoc.ie or by DM on Twitter at @GardaOmbudsman.
A protest over the death of Mr Nkecnho took place today outside Blanchardstown Garda Station.
Some of those who gathered there held up signs which read "Justice for George".
There were further protests in the Blanchardstown Shopping Centre area following the peaceful gathering at the garda station.
No incidents are under investigation at this time
The Minister for Justice Helen McEntee said the death of Mr Nkencho yesterday was "extremely traumatic" and she expressed her sympathy to everyone impacted.
Speaking on RTÉ's Morning Ireland programme, she said as well as the GSOC investigation into what happened, gardaí are also engaged with the local community.
Tánaiste Leo Varadkar also expressed his sympathies to Mr Nkencho's family, as well as those involved in the incident.
My sympathies go to the family of the young man who lost his life in Clonee yesterday. Thoughts also with the Gardai and shop workers who were involved in the incident. 1/2
— Leo Varadkar (@LeoVaradkar) December 31, 2020
The Labour Party justice spokesperson has called for a "thorough and transparent" investigation into the incident.
Brendan Howlin said this was necessary so that "all citizens and residents continue to have the highest level of trust and confidence in policing in Ireland."
