Bahraini authorities arrested suspects who have returned from Syria and are allegedly linked to "terrorist" groups, the interior ministry said on Friday.
Bahrain is among the countries that have joined the international coalition against ISIL in Syria and Iraq.
Bahrain's interior ministry announced that authorities have arrested "a group of people who were recently in Syria and are suspected of contacts with terrorist groups abroad."
It said that investigations were ongoing, without giving further details in the statement carried by the official BNA news agency.
The conflict in Syria, which began in March 2011, is believed to have drawn in thousands of foreign fighters.
Sunni militants have flocked to Syria to support the rebels, while Shiite fighters — mainly from Lebanon and Iraq — support president Bashar Al Assad's forces.
The Syrian conflict "has attracted some Bahraini citizens," the interior ministry acknowledged in February last year.
* Agence France-Presse