Shay O'Byrne was shot dead in a gun attack in Tallaght. His girlfriend suffered a gunshot wound to the leg. His murder is being linked to an ongoing bloody feud between some of Dublin's major criminal gangs based in the Crumlin and Drimnagh areas.Four people arrested over the gangland killing of a leading Dublin criminal have been released.The four - a 16-year-old girl and three men - were detained at Terenure, Tallaght and Rathfarnham garda stations. Gardai said they have been released and files are being prepared for the Director of Public Prosecutions.

John Carroll, a 33-year-old father of three, was gunned down as he sat drinking in a pub in the city centre on Wednesday night.The killing was the sixth fatal gangland-style shooting of the year
The victim of Wednesday’s attack had been living at addresses in Kilbarrack and Baldoyle in recent times, but was originally from Charlemont Street in the south inner city. He was drinking with a number of friends in Grumpy Jack’s pub in the Coombe, Dublin, shortly after 9.30pm when two men pulled up outside the premises on a blue motorbike.The pillion passenger got off the bike and went into the pub. He singled out his victim and discharged a number of shots from a handgun. The victim tried to run but was hit six times in the stomach, hip, buttocks and arm.The gunman escaped the scene on the waiting motorbike. Both the gunman and his accomplice wore helmets with dark visors pulled down throughout the attack.Carroll, who worked as a car salesman, was taken by ambulance to St James’s Hospital, where he died shortly after 11pm. He had initially been expected to survive, but is believed to have suffered a cardiac arrest.The dead man had earlier been drinking in a pub in Rialto before moving to Grumpy Jack’s. Gardaí believe Carroll was being kept under surveillance by his killers or that the gunman and his accomplice were being kept informed as to their target’s movements.
Carroll was known to gardaí for his links to the drugs trade. He was a target of the Garda National Drugs Unit for a number of years.
Gardaí believe he was centrally involved in organising drug smuggling routes from the UK and Europe for gangs operating in Ireland. He was not involved in the sale of drugs once they reached Ireland. One Garda source described him as a “freelance trafficker” who worked for very well-known drugs gangs, mostly in north Dublin, but he was not affiliated to any one gang.Gardaí believe his murder is drug-related, and are trying to establish whether Carroll was killed by a gang that owed him a large sum of money.“He was working for a number of gangs at any one time, so there would be plenty of drugs on the move and plenty of money owed,” said one Garda source.
Some of Carroll’s associates are members of a drugs gang that has recently received extortion demands from the INLA in Dublin. However, there is no firm intelligence linking Wednesday’s attack to the INLA extortionists.Gardaí are studying CCTV images of the attacker entering and leaving Grumpy Jack’s.Supt Thady Muldoon said a “mid-range” blue motorbike was used by the killers. He said the men wore dark clothing as well as dark helmets and that they escaped towards Dean Street and on to Kevin Street.

Sean Cloherty (27), known to gardai as a drug dealer, was targeted in his home on Ashcroft Grove, off the Blakestown Road in Mulhuddart. There was no sign of a struggle or forced entry. The victim, originally from Champions Avenue in the city centre, had been shot up to six times in the head, neck and chest. Cloherty was known to city centre detectives for dealing cocaine, particularly in the Temple Bar area. He was targeted by officers in the South Central Division and was arrested and taken to Pearse Street station during the summer. He had convictions for drugs, abusive behaviour and traffic offences. “Gardai have come across this man before and know his track record. He was associated with some of the big heads on the Blanchardstown scene,” said a source. A neighbour noted that Mr Cloherty, his partner and two children had only been living in the area for a short period.
The body was found slumped on a couch in the living room, and it is believed the killer calmly walked out of the house, closing the door behind him. It is likely that the gunman was either known to his victim or that he arrived at the house under false pretences and was invited inside. The weapon was probably fitted with a silencer. The grim discovery was made shortly after 8pm when a man who had a prearranged appointment to view a car for sale, looked through the living room window. He immediately contacted a doctor who arrived at the scene and the man was pronounced dead immediately. Gardai arrived on the scene shortly afterwards and the area was sealed off as top level investigators moved in. The Deputy State Pathologist Dr Michael Curtis was expected to arrive in Mulhuddart this afternoon and will carry out a post-mortem. The body will remain at the scene until a crime scene unit have completed a detailed examination of the home. The house was the subject of garda attention and had been raided by detectives exactly a week ago today. In recent months the man was said by sources to have been picked up by gardai near a heroin seizure in Louth. The victim's next door neighbour said that she was at home all yesterday evening but heard nothing. “It wasn't until all the gardai started arriving that people realised something had happened,” she said. The victim previously had an address at Champions Avenue in the north inner centre.
This year ten people have died in gangland murders in Dublin alone. Another known drug dealer from Dublin, Paddy Doyle, was shot dead near Estepona in Spain in February.

Wayne Dundon, the Dundon gang leader, was seeking 'retribution' over his own conviction. Gardai are also aware that a €50,000 'contract' is in existence for the murder of one witness. Garda sources said this weekend that there is no end in sight for the gangland war between the Dundon gang, their allies and their rivals, known as the Keane-Collopy faction. The head of the latter gang is due to be released next year after serving seven years of a ten-year sentence for possessing drugs in 2001.
Yesterday a man was shot and seriously injured in north Dublin. The shooting happened at 11.55am outside a bookmaker's on Cardiffsbridge Road in Finglas. The victim, 41, was last night in a stable condition in hospital. It is believed he was shot up to three times by a gunman who escaped on foot.

‘Dublin now resembles Chicago in the Roaring Twenties, when the gangsters were out of control,’ he said. ‘There is no joined-up strategy to fight these gangs, either at a national or international level. All of our drugs are imported, mostly by sea along Ireland’s coastline, yet we have no proper network with our fellow Europeans to patrol the seaboard. We don’t have enough boats, planes or helicopters to intercept the smuggling networks,’ he said.Gangland wars have turned Dublin into the Chicago of the 21st century, a TD and chairman of a drugs task force in the Irish capital said last night.Labour TD Joe Costello also revealed that a preliminary study by the Inner City Drugs Task Force has found that a majority of drug dealers arrested on serious offences were out on bail.Costello made his remarks following two more gangland-related murders in north Dublin this weekend. Gardai have launched a murder investigation following the fatal shooting of a 33-year-old man in Finglas early yesterday. The victim was named as Trevor Walsh, from Valley Park Road in Finglas. He had been serving a three-year prison sentence for possession of firearms, but was let out on temporary release on Thursday.The attack, which happened at about 12.20am outside a house on the Kippure Park estate, was the second fatal shooting in the capital in 24 hours.
A gunman approached the victim outside a house in the estate and shot him in the neck and chest, before fleeing the scene on a bicycle. It is understood that the killer used an automatic pistol. Walsh was taken to Blanchardstown Hospital, but was pronounced dead at 1am.The victim was associated with the late John Daly, a Dublin criminal who was shot dead last October. Walsh had been a member of a gang which specialised in importing drugs and armed robberies in the city.
It is not clear whether yesterday morning’s attack was connected to the shooting of a man in Coolock, north Dublin, on Friday afternoon. The man, named locally as 34-year-old Anthony Foster, was killed with a shotgun as he left a top-floor apartment at Cromcastle Court. Commenting on the latest gang-related shooting, Costello, who represents inner-city Dublin in the Dail, said there was no coherent plan to counter the rising number of killings.
Over the last three years there have been more than a dozen killings in north Dublin alone related to rival drugs gangs. Costello added that, while the Irish government talks tough in regard to Ireland’s gangland wars, the system remained loaded in the criminals’ favour. ‘We have found that the overwhelming majority of people arrested on serious drug offences almost all get bail and are back on the streets. The turf wars over who controls drug supplies in certain parts of Dublin have been fuelled by the easy availability of firearms and now explosives.’
Costello said the expertise of retired republican paramilitaries had been harnessed to arm and train the city’s criminal gangs.