Dundalk gardai have made a number of key arrests as part of their investigations into the murders of publican Mr Stephen Connolly and INLA man Mr Nicky O'Hare.
They have also made progress in inquiries into several other serious crimes in the town.
A man and a woman were arrested on Saturday in relation to the alleged possession of firearms and information on the possession of firearms in the early hours of July 28th, the night Mr Connolly was gunned down.
Garda sources suggest significant progress has also been made into the murder of Mr O'Hare, who is believed to have run the protection racket that killed Mr Connolly when he refused to pay. Mr O'Hare was shot dead in Dundalk three weeks after Mr Connolly's murder.
The man and woman are from Dundalk and were arrested at their home in the town. They are in their late 20s and are being held in Kells under Section 30 of the Offences Against the State Act.
The man was arrested for allegedly possessing firearms at Park Street, Dundalk on July 28th. The woman was detained for allegedly possessing information in relation to the possession of firearms at Park Street, Dundalk on the same date.
Gardai believe they may have important information on Mr Connolly's murder, which shocked the town. The murder inquiry has also looked again at an attempt on the publican's life last March during which a gang of men attempted to abduct and, gardai suspect, kill him.
Saturday's arrests are the latest in a number made in recent weeks into the murder.
Two of four other shootings which gardai have made progress in investigating were so-called "punishment shootings", in which two men had shots fired into their legs in May.
The other incidents were the firing of shots at bouncers outside a nightclub and the firing of shots through a window of Dromad Garda Station.
There has been a big welcome in Dundalk for the planned installation of close-circuit television cameras around the town, where there is growing concern about street violence.
An array of implements seized by the Garda Public Order Unit in Dundalk in recent months include a wooden club with barbed wire wrapped around it, baseball bats, sledgehammers, hammers, hatchets, crowbars, wire-cutters, wheel braces and a pellet gun.
This weekend Garda Supt Michael Staunton said: "I think CCTV will be a great crime prevention tool. I think it will primarily prevent public order offences and where they do occur, it will be a definite aid in identifying the culprits involved."
Sgt Tom Fox of the Public Order Unit said a lot of offences take place in the early hours of weekend mornings.
The Public Order unit was set up after a number of serious assaults, including stabbings, took place in the town centre area.
A bye-law introduced by Dundalk UDC in August has made drinking in public an offence. The decision by the Minister for Justice, Mr O'Donoghue, to choose Dundalk as one of the 10 provincial towns to have CCTV installed as part of a £12 million scheme has been widely welcomed.