Iran is holding and intensively grilling three suspects who entered the country from Azerbaijan to discover their role in the mid-August explosion of the power lines to the underground uranium enrichment site at Fordo, DEBKAfile’s exclusive Iranian sources reveal. Tehran is also questioning the engineers, planners and company heads who built the facility to find out why it was not provided with an independent power generator, an omission which exposed the plant to sabotage. Cutting off Fordo's power also disarmed its security system.