This is the lethal weapon recovered by heavily armed gardai after they stopped a car in south Dublin over the weekend.
The machine pistol was seized after the search of a vehicle on Saturday evening as part of an intelligence operation.
The arrest was made by the Emergency Response Unit (ERU) because of the high-risk nature of the operation involving a firearm.
A 42-year-old man from Co Wicklow was arrested and is currently being held at Shankill Garda Station. The man is being held under Section 30 of the Offences Against the State Act and can be held for up to three days.
Gardai are investigating if the weapon, an RAK machine pistol, was being dropped to associates of a Wicklow crime group. Detectives at this stage do not believe that there was an imminent threat to life.
"The arrested man isn't heavily linked to organised crime but gardai believe this machine pistol was being moved for a crime group in Wicklow," a source said.
"There is nothing to suggest a shooting was imminent but it is important that these deadly weapons are being taken out of circulation from crime gangs intent on using them."
A garda spokeswoman said the operation also involved the Garda National Drugs and Organised Crime Bureau (GNDOCB) and the Garda National Crime and Intelligence Service.
The search was part of an investigation into organised crime, the spokeswoman added.
"The seizure of firearms and the arrest of those who are prepared to use them continues to be a priority for the GNDOCB, who remain totally committed to detecting and disrupting those involved and bringing them before the courts," Detective Chief Superintendent Angela Willis said.
The garda national unit has had several success in recent weeks including drug and cash seizures.
Earlier this month detectives attached to the GNDOCB seized suspected cocaine and heroin believed to be worth around €455,000 after searches in west Dublin and the north inner city, as part of an unrelated operation.
In another separate incident, gardai supported by the Special Crime Task Force recovered more than €100,000 in cash.
Several men were also arrested after gardai intercepted two vehicles travelling along the Naas Road.