TWO handguns have been recovered by gardai investigating the murder of van driver David D'Arcy outside his home in west Dublin last month.
And three arrests were also made as officers stepped up their inquiries over the past three days into the fatal shooting, which is believed to have been carried out by members of the dissident republican group, the Continuity IRA (CIRA).
Detectives believe Mr D'Arcy's murder is linked to the shooting of Frank Nolan, who survived an attempt on his life two months earlier.
The firearms were discovered by divisional gardai during a search of a premises in Mulhuddart in west Dublin on Wednesday evening and were taken away for a detailed forensic examination at the Garda Technical Bureau in the Phoenix Park, Dublin.
Last night ballistic experts were trying to establish if either of the guns had been used in the D'Arcy murder.
A man was arrested as a result of the find and detained under section 30 of the Offences Against the State Act. He was released without charge yesterday afternoon. A file will now be prepared for the Director of Public Prosecutions.
In a follow-up operation detectives arrested a suspected senior member of the CIRA in west Dublin, and a woman, who is linked to another senior dissident, based in Limerick city.
They were detained when armed officers intercepted a car on the Naas Road on Thursday night.
The car was travelling towards Dublin when it was stopped. The man and woman were taken into custody and were still being questioned last night. Gardai think that individual members of CIRA may have got together to organise the murder rather than carrying it out as a sanctioned "hit".
Officers believe Mr D'Arcy had fallen foul of a local gang of dissidents, who had been in conflict with rival criminals in the west Dublin area.
They think that some of those involved in the dispute may have been involved in the shooting of Mr Nolan, who was hit three times in the chest with a handgun as he walked out of a premises on to Oranmore Road in Ballyfermot in September.
Mr Nolan, who had been jailed by the Special Criminal Court 11 years ago in connection with an incident in which a man had been shot in a Ballyfermot pub in 1998, survived the attack but was seriously injured.
A man, armed with a handgun, shot Mr D'Arcy as he sat behind the wheel of his van as he was about to pull out of the driveway of his home at Cherry Orchard Avenue in Ballyfermot to drive to work.
The killer and his accomplice sped off in an Opel Astra car, which was found burnt out shortly afterwards in nearby Inagh Road.
The Astra had been stolen in Limerick five days earlier.