The men are being detained in Leitrim, Longford and Roscommon.
Five men have been arrested in connection with an investigation into how illegal horsemeat made its way into the food chain.
The men are aged between 35 and 55 and are being detained at Carrick on Shannon, Longford and Roscommon Garda Stations.
In June of last year Gardai from the National Bureau of criminal Investigation raided 7 locations across the country including a meat plant, farms and houses as part of an investigation into how horse meat that should have been destroyed made its way into the food chain here.
Gardai and officials from the Department of Agriculture and The Food Safety Authority are looking into a number of cases of fraud and deception involving tampering with horse passports and microchips.
This morning 5 men were arrested on suspicion of participation in a criminal organisation.
They are being detained at a number of garda stations across the midlands.