The effects of a major power cut across Spain, Portugal and beyond are still being felt a day after the lights went out. Traffic lights switched off, trains stopped, and airports went dark in several cities, including Madrid, Barcelona, Valencia, Seville in Spain and Lisbon, Santarém and Porto in Portugal, following the outage around midday Monday.

BARCELONA, Spain (AP) — A blackout brought much of Spain and Portugal to a standstill Monday, halting subway and railway trains, cutting phone service and shutting down traffic lights and ATMs for millions of people across the Iberian Peninsula.

Spain and Portugal are reeling from a massive, unexplained power outage that knocked out traffic lights, caused chaos on roads and in airports, and prompted both countries to declare a state of emergency.