Spain says blackout caused by multiple technical factors and not a cyber attack

The outage disrupted businesses, transport systems and mobile networks (Manu Fernandez/AP)

Six weeks after Spain and Portugal suffered a massive power outage, authorities in Madrid have issued an official report saying the cascading blackout that left tens of millions disconnected in seconds was caused by technical and planning errors that led to the grid’s failure.

Spanish ecological transition minister Sara Aagesen, who manages the nation’s energy policy, said at a press conference that small grid failures, concentrated in the south of Spain, led to a chain reaction among larger ones, while completely ruling out questions about a cyber attack.