The getaway car used in the murder of Eddie Hutch on Monday night was not stolen and "significant progress" has been made in tracing its owner, gardaí have said.
The silver BMW was later recovered near the scene with a petrol can inside, a clear indication of an intention to destroy it but gardaí believe the killers were forced to make a hasty escape.
It is one of three vehicles - the others being a black Peugeot and a dark coloured jeep, either an Isuzu or a Toyota Landcruiser - identified as being of interest to detectives.
Gardaí have not commented on the motive for the shooting dead of Hutch at his home in Poplar Row in north inner-city Dublin at 7.46pm, but it is believed to be a retaliatory hit following the shooting dead of David Byrne in the Regency Hotel on Friday.
Hutch, who was gunned down while his partner was in the house, was considered a "soft target". He was the brother of Gerry Hutch, known as "The Monk".
A number of shots were fired from handguns but gardaí could not say how many until they receive the results of a post-mortem examination.
"We are very interested in four masked men who were seen in the location, two of whom fired shots that resulted in the death of Mr Hutch," said Assistant Garda Commissioner Jack Nolan at a briefing on Tuesday evening.
“We had no specific intelligence that Mr Hutch was at risk.
“This was, once again, a very horrific incident and we are appealing for all information.”
Of particular interest is the silver BMW, registration 06 G 8965, which left the scene of the murder and travelled along the Drumcondra Road and into St Patrick’s Parade where it was abandoned.
Gardaí believe this was done in haste due to the large number of garda in the area and their rapid response, arriving on the scene within two minutes of the reported gunfire.
The black Peugeot was seen in the area but it is unclear if it was involved.
“We believe that when the BMW vehicle was abandoned that the raiders then left in the dark Isuzu jeep or Toyota Landcruiser vehicle,” said Mr Nolan, who said it then travelled in the direction of Glasnevin.
“A full forensic and technical and DNA examination has been conducted on the silver BMW and all of the contents.
“We would appeal to any retail outlets who sold petrol to anybody in a drinks type bottle to please get in touch.”
He declined to comment on the possible presence of a bullet hole in the rear window of the car.
Gardaí are now focused on prevention with enhanced patrolling in a situation they have described as “fluid and dynamic”.
They said “significant assistance” had been received from the local community since the shooting.
Their attention will be sharply focused on the forthcoming funerals of Hutch and Byrne among general fears of further gang retaliation.
“An Garda Siochana will prepare a very detailed operational plan in relation to the funerals of the deceased people that have died in the last couple of days. You can rest assured on that,” said Mr Nolan.
“An Garda Siochana has done this many times before in similar or related types of incidents.”
Anybody with any information, or who may have seen any of three vehicles described, is asked to contact gardai at Store Street on (01) 666 8000 or any other station.