Three men have been arrested after gardaí discovered a large cannabis growing facility at a dry cleaners in Dublin city.

Officers from the Garda National Drugs Unit raided a dry cleaners in Drumcondra this afternoon and found a sophisticated lighting and irrigation system for growing cannabis on three floors.

Around 1,000 plants with an estimated street value of over €400,000 were seized.

Two men, aged in their 30s, were arrested at the scene. A third man, in his late 20s, was arrested this evening in the Drumcondra area in connection with the discovery.

All three are being questioned at Bridewell Garda Station.