The Ministry of Interior announced details of the operation against the Ashtar Brigade in the northeastern village of al-Dair on Thursday.
The Ashtar Brigade has claimed a number of bombings and attacks in the Sunni-ruled country, which hosts the US Navy's 5th Fleet.
The ministry says more than 50 kilograms of high-grade explosives and other materials including bomb-making diagrams and ammunition were seized in the raid. It was not immediately clear when the arrests took place.
Bahrain has been roiled by years of low-level unrest following a 2011 uprising led by its majority Shiites against the Sunni monarchy.