Gunmen who killed mum Baiba suspected of gang hit on The Monk's brother
Members of the gang involved in the murder of taxi driver Eddie Hutch Snr are also suspected for the shooting dead of a young mother of two in Dublin nine years ago.
Baiba Saulite was gunned down in November 2006 as she smoked a cigarette at her front door while her two young sons slept inside, in a crime that shocked the nation.
The two killers were close confidantes of Martin 'Marlo' Hyland - the Dublin crime boss who was himself executed a month later.
Hyland recruited the men, who were both in their early 20s at the time, to carry out the murder on behalf of Limerick gangster John Dundon - who is now serving life for the murder of innocent rugby player Shane Geoghegan.
Gardaí now suspect the same pair were among the four-member hit team sent to kill Eddie Hutch Snr, the older brother of crime boss Gerry 'The Monk' Hutch on Monday.
The hit team exacted brutal revenge for the execution of rival criminal David Byrne in the Regency Hotel attack last week.
And a third suspect is a well-known killer who was hired by the Kinahan cartel for a number of gangland murders in Dublin. He is believed to be the would-be assassin who shot and seriously injured John Gilligan in a murder bid in February 2014.
He is also the prime suspect for the subsequent murder of Gilligan's minder, Stephen 'Dougie' Moran.
Heavily armed members of the Emergency Response Unit (ERU) have been patrolling streets in the north and south inner city since Monday night. Officers privately admit they are shocked by the events.
Up to 40 key criminals are under surveillance by gardaí. In recent months, many have been warned that their lives are under threat.
Taoiseach Enda Kenny yesterday said he had "full confidence" in Garda Commissioner Nóirín O'Sullivan's ability to tackle gangland crime. He also said he did not think new laws were necessary to deal with the issue.
"I don't believe that particular special powers will be required here. The gardaí and the special units - the emergency response unit - have dealt with this on other occasions in the country in a period of years and before in Dublin.
"I expect that the high visibility of policing that we've now followed through - I hope that that will yield results and that the persons who were involved in this ferocious internal gangland spate of murders will be brought to justice.
"We support the commissioner and the Garda in the job they have to do here," he added.
Tensions between the Kinahan and Hutch factions have been at breaking point since the murder of The Monk's nephew last September.
It has emerged that Christy Kinahan Senior and Gerry Hutch had previously agreed that nothing would happen to Gary Hutch after he was accused of being a police informant.
Sources revealed that agreement was reached six weeks before the murder - when The Monk travelled to Schipol Airport in Amsterdam to meet his former friend.
Worried that they had bitten off more than they could chew, the Kinahan gang sued for peace with the Hutch side.
Daniel Kinahan travelled to Dublin three times to meet with Gary Hutch's associates but was rebuffed each time.
In December, Daniel Kinahan had arranged to meet face-to-face with Gerry Hutch in a hotel near Dublin Airport but The Monk never showed.
Kinahan had been accompanied by the hitman and he later made it known he considered the no-show the final snub.
Meanwhile, gardaí are still searching for a close associate of Gary Hutch who has been identified in photographs taken shortly after the Regency Hotel attack last Friday.
The man, who is in 20s and from the north inner-city, was dressed as a woman.
A second man, who is stocky and wearing a cap, is also believed to have been identified and is thought to be from Northern Ireland.
The two men were part of a five-man hit squad - two of them were armed with AK47s and were wearing fake garda uniforms when they stormed the lobby of the hotel.