Guns, ammunition and drugs have been seized following separate Garda operations in Dublin, Limerick and Louth.
On Wednesday, Gardaí at Roxboro Road in Limerick conducted a planned search operation at a halting site in Southill.
A gun, shell casings and ammunition were all seized.
This search was conducted following an earlier response to reports on Tuesday of a gun being fired at the halting site.
Gardaí say no arrests have been made and investigations are ongoing.
On Thursday, officers discovered two semi-automatic .22 calibre pistols and 20 rounds of .22 ammunition at a premises in the Greenhills Road area of Tallaght.
This was part of ongoing intelligence-led investigations targeting organised crime activity in Dublin.
A large quantity of cannabis, cocaine and diazepam tablets were also seized.
These have an estimated total street value of over €1m.
A woman, aged 49, was arrested under section 30 of the Offences Against the State Act and is being detained at Tallaght Garda station.
While on Friday, officers stopped a car on the Main Road area of Tallaght.
During a search of the vehicle, two semi-automatic 9mm pistols and approximately 25 rounds of 9mm ammunition were seized.
A male, age 36, was arrested under section 30 of the Offences Against the State Act.
He is being detained at Crumlin Garda station.
Separately in Louth, cannabis resin with an estimated street value of over €40,000 was seized.
It was discovered in a search of a Drogheda premises.
One 34-year-old woman was arrested on suspicion of drug trafficking, and is being in Drogheda Garda station under Section 2 of the Criminal Justice Act.
Assistant Commissioner John O'Driscoll says: "The Garda Síochána continues to engage in targeted operational activity, with a view to dismantling organised crime groups.
"The seizure of firearms and the arrest of those who possess them, is a particular target."