It has emerged that an armed garda patrol was around the corner from a Dublin pub, as a 35-year-old man was shot and murdered last night.
It was one of two fatal shootings in the capital yesterday, and gardaí say they are following every line of inquiry in connection with both crimes.
35-year-old Michael Barr was shot a number of times as he drank in Sunset House in Summerhill around 9.30pm last night.
Gardaí are focusing on a potential getaway car.
They say a silver, Cork-registered Audi was recovered in nearby Drumcondra and has been seized for technical exam.
That car is linked to another silver saloon car which left Walsh Road in Drumcondra in the direction of Home Farm Road with three men inside.
In a separate shooting, 37-year-old Thomas Farnham was killed at a house on Kilcronan Court in Clondalkin just before midnight, but it is not thought the two crimes are related.
Gardaí say it appears that a lone male entered the hallway of the house and fired a number of shots, fatally injuring Mr Farnham.
He was pronounced dead at the scene.
The lone male then left the scene and is believed to have ran along Kilcronan Close onto the Grand Canal - and then exited onto the green area towards Lock View Road.
He is described as wearing all black clothing, black runners, black tracksuit and may have been wearing a balaclava - he is also described as being short in height.
Speaking at the GRA conference in Co Kerry, Garda Commissioner Noirin O'Sullivan condemned the murders and paid tribute to the communities affected.
While Assistant Garda Commissioner, John O'Mahoney, says a number of lines of inquiry are also being looked at for the Summerhill shooting.
He says officers are constantly working off intelligence-led information, to prevent murders.