The two gunmen who shot Nicholas O'Hare last Saturday night made sure he had no chance of survival. When their 6ft 4in victim fell to the ground after the first shot, they stood over him and discharged a further eight bullets into his head and neck.

The attack followed the killing of 26-year-old publican Stephen Connolly on July 28th. He was shot by a masked gunman in front of his former girlfriend as he sat in a parked car.

It is believed he was killed because he refused to pay local criminals £600-per week protection money and a large down payment.

Nicholas O'Hare, known as "Mad Nicky", was one of five men questioned by gardai following an earlier attempt on Connolly's life in March, when a masked gang tried to bundle him into a van and fired shots. However, he managed to escape. No arrests had been made over his killing last month, but this gang were prime suspects.

The five-member gang all have connections with the splinter republican group, the Irish National Liberation Army, and include the local INLA officer in command, who is nicknamed "Jaws". He has been arrested twice on suspicion of playing a role in the Omagh bombing.

The Irish Republican Socialist Party, the political wing of the INLA, this week issued a statement denying that O'Hare was a member at the time of his death and claiming he had been dismissed some time ago. However, according to security sources he was a member of the INLA gang.

Gardai believe trouble began for Connolly when, on their advice, he attempted to rid his bar, the Carlton, of certain clientele, among them a leading Dundalk drug figure who associated with O'Hare. It is thought this man went to O'Hare, who then instigated the demands for payments. On the night Connolly was killed, locals say, O'Hare was "staring him out of it" as both men socialised in a town centre pub. O'Hare had a history of preying on people he considered vulnerable. Last year, after the killing of drug-dealer Brendan Fagan in a Newry bar, O'Hare targeted a Dundalk man for extortion when he found out he was an associate of Fagan's and was with him in the bar when he was shot. O'Hare calculated the associate had money and gave him a severe beating on Annagassan strand, south of Dundalk, before forcing him to hand over about £5,000.

This week Chief Supt Michael Finnegan dismissed reports that O'Hare had been running a large protection racket in Dundalk. He said the evidence indicated it was "small scale" and confirmed that Connolly had come under pressure from a criminal gang with INLA links.

"I've been asked if these two killings were professional hits and I'll tell you there is nothing professional about what has been going on here for the past three weeks. It's just sheer gangsterism. There's absolutely nothing professional about wearing a disguise and shooting a man dead. It's cowardly," he said. Chief Supt Finnegan said the two murder investigations were continuing, and the possibility that they were linked was being examined, "but we have nothing concrete to connect them at this stage".

Gardai believe O'Hare (34), from Andersonstown, west Belfast, who moved to Dundalk in 1986, was not the gunman in the July attack. But it is understood they have narrowed their list of suspects to three men, including two members of the gang and a third older associate. However, the identity of the two gunmen who killed O'Hare is far from clear, and gardai have stressed that many people were armed with the motive to kill O'Hare and the timing with Connolly's death could have been used to "muddy the waters".

Sources close to the investigation admit detectives have thrown the net wide.

"It could have been the Provos, but that's unlikely. It could have been the INLA - that hasn't been ruled out. It could have been a direct revenge attack for Connolly's killing, or a Dublin criminal gang in revenge for Patrick Neville's death."

The heavy-set, red-haired O'Hare was a familiar face to gardai all over the State and had been arrested many times. He was also well known to pub and club owners throughout Cos Louth, Meath and Dublin. He supplied them with bouncers in a lucrative door security business.

He began associating with the INLA at a young age and was a good friend and former housemate of Dessie O'Hare, who is serving a prison sentence for the kidnap of dentist John O'Grady.

Nicholas O'Hare was first arrested in 1986 after an armed robbery in Kingscourt, Co Cavan, and later began his activities in Dublin as the doorman of a snooker club in Amiens Street, which was raided in 1989 and a sawn-off shotgun and cartridges recovered. O'Hare was sentenced to four years.

On his release he became involved in attempts to extort £48,000 from the owner of a Dublin amusement arcade and was charged for his role in the scheme. He jumped bail during the case and seriously assaulted his father who lives in Co Meath. In 1993 he was convicted of charges relating to both incidents and completed another prison sentence before returning to Dundalk.

By the mid-1990s he was wanted for questioning in the North over several armed robberies at isolated post offices along the Border. Gardai also believe he was linked to the robbery of the Omeath post office in 1996, although he was never charged.

He twice assaulted gardai, the first incident in 1988 when he head-butted an off-duty garda and punched another in the face at a disco in the Imperial Hotel, Dundalk. In a second attack he punched a uniformed garda in the face in a Dundalk shopping centre and was given an 18-month suspended sentence.

Only days before his death O'Hare was questioned at Kevin Street Garda station about the killing of small-time criminal Patrick Neville in Inchicore last April. The shooting was seen as a revenge killing for the death of a Belfast INLA man, Patrick Campbell, who died last November after being bludgeoned to death in a fight in the Ballymount Industrial Estate.

A disagreement over damage to an INLA man's car had led to a fight with a Dublin criminal gang. Six members of the criminal gang were held prisoner, stripped naked and severely beaten by the INLA gang that included O'Hare.

More members of the Dublin gang arrived and overpowered the INLA men, ending in Campbell being killed.

However, detectives investigating his death are understood to believe it unlikely that a Dublin gang would come to Dundalk to kill O'Hare. He had been in Dublin the night before his death, and it would be more likely that, if they wished to kill him, it would be done on "home turf" in Dublin.

The line of inquiry that O'Hare was killed as direct revenge for Connolly's death is also being considered. Connolly, who originally came from Jonesboro, Co Armagh, was involved in a car business across the Border and has family links in the Newry area.

O'Hare's relationship with the INLA leadership appears to have been fraught in the past and he was given a severe at the hands of the organisation in 1996.

This week the IRSP moved to distance itself from O'Hare and in a statement claimed he had been dismissed some time ago for "nefarious activities" that brought the organisation into disrepute.

An IRSP spokesman in Belfast said it was "implicit" in the statement that the INLA was not responsible for the killing. He said it was unclear who was responsible but the organisation would be examining whether the shooting was designed as an attack on it as a whole rather than just on O'Hare. "The people responsible may not have been aware that he was not a member," he added.

Last October two INLA men were shot in Dundalk in what appeared to be an internal "punishment" attack over money. One of the victims of the attack has since returned to Belfast. Gardai suspect that if the INLA did kill O'Hare, it could have been a revenge killing for that attack. "The speculation that he was killed because they couldn't control him doesn't really stand up, because it was often very handy for them to have a `Mad Nicky'," said one garda.

O'Hare's remains were brought back to his native Belfast this week for burial, and no paramilitary trappings were visible at his funeral. He had not been North to see his family for many years because he knew he would be arrested.