Power restored in Spain and Portugal but reason for blackout remains a mystery

The reason behind the massive blackout that had hit Spain and Portugal on Monday remained unclear, with some isolated disruptions persisting on the following day after the majority of power was restored.

One of the biggest power outages in Europe grounded flights, paralysed train services, disrupted mobile communications and caused ATMs to shut down across the Iberian Peninsula.

By 11 am CET on Tuesday, the Spanish electrical system was reported to be operating normally, according to electricity operator Red Eléctrica. The Portuguese grid operator REN confirmed that power had been restored to all 6.4 million customers.