The Spanish power distributor calls it “exceptional and extraordinary.” Power went down just after noon and by nightfall only half of the power had been restored in Spain. The cause was not immediately clear Monday.

The complete restoration of electricity in Spain and Portugal might take between six to ten hours following a widespread blackout that left millions

Spain has experienced a power outage that has affected much of the country and the world. The causes of the blackout are still being investigated, although work is already underway