Spain and Portugal's power is almost fully restored, but the huge blackout's cause remains a mystery

MADRID (AP) — Power was almost fully restored to Spain and Portugal on Tuesday although many questions remained about what caused one of Europe’s most severe blackouts that grounded flights, paralyzed metro systems, disrupted mobile communications and shut down ATMs across the Iberian Peninsula. By 7 a.m., more than 99% of energy demand in Spain had been restored, the country's electricity operator Red Eléctrica said. Portuguese grid operator REN said Tuesday morning all of th