Cannabis plants with an estimated street value of €4.6m have been recovered by gardaí in a series of raids on so-called grow houses around the country.
A total of 5,800 plants were seized in a number of raids as part of Operation Nitrogen, an intelligence-led operation by the Garda National Drugs Unit.
Eight people were arrested and are being held in various garda stations around the country.
Almost 2,000 of the cannabis plants are believed to have been seized in Longford town and south Roscommon.
A man in his 20s was arrested following the discovery and is currently being questioned at Roscommon Garda Station.
A further three of the arrests were made at a commercial premises in Longford town, the suspects being held at Longford and Mullingar Garda Stations.
