Last Friday and Saturday, private investigators made purchases of contraband tobacco in Tralee, Killarney and Dingle.
The operation was mainly focused in the county town to coincide with the Rose of Tralee Festival.
The test purchase operation was carried out on behalf of cigarette company, Philip Morris International.
Retired Detective Garda Chief Superintendent Kevin Donohoe was involved in this Kerry operation and a previous one carried out during Puck Fair in Killorglin.
He says groups linked to the illegal trade include dissident Republicans, homegrown criminals and Eastern European gangs.