Three guns were recovered after a car was stopped by Gardai in Castlerea last night.
As a result of an operation into illegal crime gang activities, Gardai attached to the Roscommon / Longford division stopped a car on Main Street in the town at about 8.30pm, and found three fully loaded pistols.
The firearms were seized and will be forwarded to the forensic laboratory for analysis.
A man in his early 30's was arrested at the scene, and is being detained at Castlerea Garda Station under Section 30 of the Offences Against the State Act, for unlawful possession of firearms.
Gardai conducted follow-up searches at a location in Castlerea town last night, during which a small quantity of heroin was seized.