Eight people are still undergoing garda questioning following the fatal shooting of a man in Limerick on Tuesday evening.
Daniel Fitzgerald (24), a carpenter, suffered a number of gunshot wounds after a gunman opened fire on him at his home in Cloughnadromin, Ballysimon, Co Limerick.
Gardaí confirmed yesterday that an eighth person, a 17-year-old male, was arrested on Wednesday night in the Newcastle West area.
Seven people, including two teenage girls, were arrested earlier in the day following Mr Fitzgerald's shooting.
The murder, which gardaí say is not connected to the wider Limerick feud, took place shortly after 9.30pm on Tuesday.
It is understood the killing may be linked to an arson attack on a vehicle the previous night which took place at a house in the area.
Gardaí are also investigating whether or not a shooting at a house in Fairview Crescent in Limerick city early on Tuesday morning is linked to the murder.
Mr Fitzgerald, who was living in a caravan beside the cottage where the shooting took place, was taken to the Midwestern Regional Hospital, Limerick, where he was pronounced dead a short time later.
A number of the victim's relatives were present at the time of the shooting but escaped unharmed when the gunman fired at least 10 shots.
It is understood the dead man, who was single and had no children, was struck a number of times and suffered one gunshot wound to the head.
His parents, who live in Belfast, were making their way to Limerick following their son's death.
State Pathologist Dr Marie Cassidy also travelled to Limerick to carry out a postmortem on the deceased.
Members of the Keane/Collopy Limerick criminal gang were among those in custody last night.
A 19-year-old man who is a leading member of the gang was arrested along with a 38-year-old woman and two teenage girls about an hour after the murder took place.
The four, who are related, were all arrested at the same house, which is close to the scene of the fatal shooting.
Three other males, aged from late teens to early 20s, were arrested in Limerick city in connection with the murder yesterday afternoon.
All eight suspects were being held last night under section 50 of the Criminal Justice Act.
Speaking at a press briefing in Limerick, Supt Ann Marie McMahon – who is leading the murder inquiry – said significant progress had been made in the case.
Moreover, while she would not be drawn on a motive for the killing she insisted it was not linked to the wider Limerick feud.
Supt McMahon said the victim, whom she described as "hardworking", had not come to the attention of gardaí before.
"The victim is a very hardworking man, a man in his mid-20s and this is a very tragic event," she said.
"This investigation is very much in its infancy and obviously we are exploring all avenues of inquiry," she continued.
The scene of Tuesday night's shooting remained sealed off and technical examinations are continuing.
A special incident room has been set up at Roxboro Garda station, which can be contacted at 061-241340.