Gardaí believe the murder of Noel Kirwan last week was carried out by men who have been involved in feuding in Dublin since the late 1990s that has cost the lives of almost 30 people.
The 62-year-old father of four was gunned down in west Dublin last Thursday, the 11th victim of the so-called Kinahan-Hutch feud.
Gardaí believe men who had previously been involved in a feud between rival factions in the Dublin suburbs of Crumlin and Drimnagh, to which around 16 murders have been attributed, are now members of the Kinahan gang.
And they believe those men have been central players in the shooting dead of a number of victims of the Kinahan-Hutch feud this year, including that of Kirwan last Thursday.
It means a small group of suspects working for Christy Kinahan have been involved in gun feuding in Dublin, almost uninterrupted, since the late 1990s in which almost 30 people have died, most of them in Dublin.
To date 11 people have been shot dead as part of the Kinahan-Hutch feud, all but one carried out by the Kinahan side.
The precise death toll in the Crumlin-Drimnagh feud is put at 16 by many Garda sources. However, the motive for other murders has never been determined, meaning the death toll could be higher.
Some of the men in the gang regarded as having won the Crumlin-Drimnagh feud – mainly because their key rivals were murdered or jailed – are now central to the Kinahan cartel’s operation in Dublin.
While involved in the Crumlin-Drimnagh feud they sourced drugs for Christy Kinahan and were regular visitors to him and his cartel in the south of Spain.
And in the years since the Crumlin-Drimnagh feud dissipated, they have climbed the underworld hierarchy and are now some of Kinahan’s key players in Dublin.
These Dublin-based men knew Noel Kirwan well and enjoyed good relations with him from the period dating back to their childhoods.
However, though they had never been in direct conflict with him it appears they were angered by Kirwan's attendance at the funeral of Eddie Hutch in Dublin in February.
Kirwan had known Eddie Hutch and his brother Gerry Hutch, also known as The Monk, as well as other members of the family.
He attended the funeral of Eddie Hutch, who was murdered as part of the Kinahan-Hutch feud, as a family friend.
However, because the men previously involved in the Crumlin-Drimnagh feud are now part of the Kinahan-Hutch feud, they regarded Kirwan’s presence at the Eddie Hutch funeral as an affront.
It is believed Kirwan was murdered because in the eyes of his killers he had offered his support to their rivals. And his role in advising Hutch appears to have also been part of the motive for his killing.
He was shot dead as he sat in his car in the driveway of his partner's house in St Ronan's Drive, Clondalkin, just after 5pm last Thursday. His partner was also in the vehicle but was uninjured.
Kirwan had strong links to the Provisional IRA, dating back to when he was in his 20s, and had been part of the vigilante movement against Dublin drug dealers in the 1990s.
However, he was not regarded as a gang member on the Hutch side. He did not believe his life was at risk and was not regarded among a group of between 20 and 30 men at risk of being shot as part of the feud.