Gardaí investigating the murder of Stephen O'Halloran who was shot dead in Tallaght on Monday night believe they have recovered the murder weapons.
Two 9mm handguns were discovered in a garden near Kilmartin Drive, where the 20-year-old was shot dead as he sat in a car in the driveway of his home.
Gardaí in Finglas investigating the activity of organised criminal gangs have also recovered two more handguns.
They were discovered this evening in a series of searches.
Gardaí also recovered €80,000 worth of heroin.